1

Temperature

Temperature

bull is a measure of how hot or cold an object is compared to another object

bull indicates that heat flows from the object with a higher temperature to the object with a lower temperature

bull is measured using a thermometer

2

Temperature Scales

Temperature Scales

bull Kelvin

bull Celsius

bull Fahrenheit

3

A What is the temperature of freezing water

1) 0degF 2) 0degC 3) 0 K

B What is the temperature of boiling water

1) 100degF 2) 32degF 3) 373 K

C How many Celsius units are between the boiling and freezing points of water

1) 100 2) 180 3) 273

Learning Check

Temperature conversions

Celsius to Kelvin K = deg C + 273

Kelvin to Celsius deg C = K - 273

Celsius to Fahrenheit F = 95 ( deg C) + 32

Fahrenheit to Celsius C = 59 (deg F - 32)

Kelvin to Fahrenheit deg F = 95 (K - 273) + 32

Fahrenheit to Kelvin K = 59 (deg F - 32) + 273

5

Temperatures

TABLE 25

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

2

Temperature Scales

Temperature Scales

bull Kelvin

bull Celsius

bull Fahrenheit

3

A What is the temperature of freezing water

1) 0degF 2) 0degC 3) 0 K

B What is the temperature of boiling water

1) 100degF 2) 32degF 3) 373 K

C How many Celsius units are between the boiling and freezing points of water

1) 100 2) 180 3) 273

Learning Check

Temperature conversions

Celsius to Kelvin K = deg C + 273

Kelvin to Celsius deg C = K - 273

Celsius to Fahrenheit F = 95 ( deg C) + 32

Fahrenheit to Celsius C = 59 (deg F - 32)

Kelvin to Fahrenheit deg F = 95 (K - 273) + 32

Fahrenheit to Kelvin K = 59 (deg F - 32) + 273

5

Temperatures

TABLE 25

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

3

A What is the temperature of freezing water

1) 0degF 2) 0degC 3) 0 K

B What is the temperature of boiling water

1) 100degF 2) 32degF 3) 373 K

C How many Celsius units are between the boiling and freezing points of water

1) 100 2) 180 3) 273

Learning Check

Temperature conversions

Celsius to Kelvin K = deg C + 273

Kelvin to Celsius deg C = K - 273

Celsius to Fahrenheit F = 95 ( deg C) + 32

Fahrenheit to Celsius C = 59 (deg F - 32)

Kelvin to Fahrenheit deg F = 95 (K - 273) + 32

Fahrenheit to Kelvin K = 59 (deg F - 32) + 273

5

Temperatures

TABLE 25

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Temperature conversions

Celsius to Kelvin K = deg C + 273

Kelvin to Celsius deg C = K - 273

Celsius to Fahrenheit F = 95 ( deg C) + 32

Fahrenheit to Celsius C = 59 (deg F - 32)

Kelvin to Fahrenheit deg F = 95 (K - 273) + 32

Fahrenheit to Kelvin K = 59 (deg F - 32) + 273

5

Temperatures

TABLE 25

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

5

Temperatures

TABLE 25

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Characteristic of

Gases

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

The Nature of Gasesbull Gases expand to fill their containers

bull Gases are fluid ndash they flow

bull Gases have low densityndash 11000 the density of the equivalent liquid or

solid

bull Gases are compressible

bull Gases effuse and diffuse

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gases Are Fluids

bull Gases are considered fluids

bull The word fluid means ldquoany substance that can flowrdquo

bull Gas particles can flow because they are relatively far apart and therefore are able to move past each other easily

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gases Have Low Densitybull Gases have much lower densities than liquids

and solids do - WHY ndash Because of the relatively large distances between

gas particles most of the volume occupied by a gas is empty space

bull The low density of gases also means that gas particles travel relatively long distances before colliding with each other

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gases are Highly Compressiblebull Suppose you completely fill a syringe with liquid and

try to push the plunger in when the opening is plugged ndash You cannot make the space the liquid takes up become

smaller

bull The space occupied by the gas particles is very small compared with the total volume of the gas

bull Applying a small pressure will move the gas particles closer together and will decrease the volume

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gases Completely Fill a Container

bull A solid has a certain shape and volume

bull A liquid has a certain volume but takes the shape of the lower part of its container

bull In contrast a gas completely fills its container

bull Gas particles are constantly moving at high speeds and are far apart enough that they do not attracteach other as much as particles of solids and liquids do

bull Therefore a gas expands to fill the entire volume available

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gas Pressure

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gas Pressurebull Earthrsquos atmosphere commonly known as air is a mixture

of gases mainly nitrogen and oxygen

bull As gas molecules are pulled toward the surface of Earth they collide with each other and with the surface of Earth more often Collisions of gas molecules are what cause air pressure

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Measuring Pressure

Pressure = Area

Force Newton (N)

m2 cm2

Units of Pressure

1 atm = 760 torr = 1013 kPa = 760 mmHg

Standard Temperature Pressure (STP)

1 atm 0degC 224 L 1 mole

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

100 atm 760 mmHg = 760 x 10^2 mmHg

1 Covert 100 atm to mmHg

1 atm

300atm 1013 kPa = 304 kPa

2 Covert 300 atm to kPa

1 atm

3 What is 1000 KPa in atm

1000 kPa

1013 kPa = 09872 atm

1 atm

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

bull Measures atmospheric pressure

bull The atmosphere exerts pressure on the surface of mercury in the dish

bull This pressure goes through the fluid and up the column of mercury

bull The mercury settles at a point where the pressure exerted downward by its weight equals the pressure exerted by the atmosphere

Measuring Pressure Using Barometer

Gas Theory

Kinetic Molecular Theorybull Particles of matter are ALWAYS in motionbull Volume of individual particles is zerobull Collisions of particles with container walls cause pressure

exerted by gasbull Particles exert no forces on each otherbull Average kinetic energy is proportional to Kelvin

temperature of a gas

bull Ideal gas- imaginary perfect bull gas fitting the theory

Checking for understanding

List 5 characteristics of gases

1

2

3

4

5

List 5 characteristics of gases according to the KMT

1

2

3

4

5

Gas Laws

Measurable Properties of Gases

Gases are described by their measurable properties

bull P = pressure exerted by the gas

bull V = total volume occupied by the gas

bull T = temperature of the gas

bull n = number of moles of the gas

atm

Units

L

K

mol

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Kinetic Molecular Theorybull Particles of matter are ALWAYS in motionbull Volume of individual particles is zerobull Collisions of particles with container walls cause pressure

exerted by gasbull Particles exert no forces on each otherbull Average kinetic energy is proportional to Kelvin

temperature of a gas

bull Ideal gas- imaginary perfect bull gas fitting the theory

Checking for understanding

List 5 characteristics of gases

1

2

3

4

5

List 5 characteristics of gases according to the KMT

1

2

3

4

5

Gas Laws

Measurable Properties of Gases

Gases are described by their measurable properties

bull P = pressure exerted by the gas

bull V = total volume occupied by the gas

bull T = temperature of the gas

bull n = number of moles of the gas

atm

Units

L

K

mol

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Checking for understanding

List 5 characteristics of gases

1

2

3

4

5

List 5 characteristics of gases according to the KMT

1

2

3

4

5

Gas Laws

Measurable Properties of Gases

Gases are described by their measurable properties

bull P = pressure exerted by the gas

bull V = total volume occupied by the gas

bull T = temperature of the gas

bull n = number of moles of the gas

atm

Units

L

K

mol

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Gas Laws

Measurable Properties of Gases

Gases are described by their measurable properties

bull P = pressure exerted by the gas

bull V = total volume occupied by the gas

bull T = temperature of the gas

bull n = number of moles of the gas

atm

Units

L

K

mol

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Measurable Properties of Gases

Gases are described by their measurable properties

bull P = pressure exerted by the gas

bull V = total volume occupied by the gas

bull T = temperature of the gas

bull n = number of moles of the gas

atm

Units

L

K

mol

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Gas Laws ndash ABCGG LAWS

bull Abull Bbull Cbull G

bull G

vogadrorsquos

oylesrsquos

harlesrsquos

ay- Lussacrsquos

n is proportional to V constant T

P is inversely proportional to V constant T

V is proportional to T constant P

P is proportional to T constant V

rahamrsquos Rate of effusion is inversely proportional to square root of gasrsquos molar mass

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

Pressure-Volume Relationship Boylersquos Law

bull Pressure and Volume are inversely proportional at constant temperature

bull Pressure = Volume (when one increases the other one decreases)

bull Volume = Pressure

PV = k

P1V 1= P2V2

For ALL calculations

1 Circle the numbers underline what you are looking for

2 Make a list of number you circled using variables

3 Write down the formula4 Derive the formula to isolate the variable

you are looking for5 Plug in the numbers6 Answer according to significant figures

Boylersquos Law CalculationA given sample of gas occupies 523mL at 100 atm The pressure is increased to 197 atmwhile the temperature stays the same What is the new volume of the gas

P1V 1= P2V2

P1= 100 atm P2= 197 atm

V1= 523 mL V2= mL

V2=P1V1

P2

= (100 atm) (523 mL)

(197 atm)

= 265 mL

1 A sample of oxygen gas has a volume of 1500mL at a pressure of 0947 atm What will the volume of the gas be at a pressure of 100 atm if the temperature remains constant

P1V 1= P2V2

P1= 0947 atm P2= 100 atmV1= 1500 mL V2= mL

V2=P1V1

P2

=(0947atm) (1500 mL)

(100atm)

= 142mL

2 If 25 L of a gas at 1100 kPa is expanded to 40 L at constant temperature what will be the new value of pressure

P1V 1= P2V2

P1=1100 kPa P2= kPa

V1= 25 L V2= 40 L

P2=P1V1

V2

=(1100 kPa) ( 25 L)

(40 L)

= 69 kPa

Real World Application BOYLErsquoS LAW

bull Syringes and turkey basters are operated by Boyles Law pulling back on the plunger increases the volume inside the syringe which decreases the pressure which then corrects when liquid is drawn into the syringe thereby shrinking the volume again

bull Spray cans like spray paint and air freshener are governed by Boyles Law intense pressure inside the can pushes outward on the liquid inside the can trying to escape and forces the liquid out when the cap makes an opening

bull You breathe because of Boyles Law

bull Balloons work because of Boyles Law

bull A car (combustion) engine works when the sudden increase in pressure from the combustion of the fuel expands the cylinder and pushes on the piston causing the crankshaft to turn

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

Boylersquos Law CalculationA given sample of gas occupies 523mL at 100 atm The pressure is increased to 197 atmwhile the temperature stays the same What is the new volume of the gas

P1V 1= P2V2

P1= 100 atm P2= 197 atm

V1= 523 mL V2= mL

V2=P1V1

P2

= (100 atm) (523 mL)

(197 atm)

= 265 mL

1 A sample of oxygen gas has a volume of 1500mL at a pressure of 0947 atm What will the volume of the gas be at a pressure of 100 atm if the temperature remains constant

P1V 1= P2V2

P1= 0947 atm P2= 100 atmV1= 1500 mL V2= mL

V2=P1V1

P2

=(0947atm) (1500 mL)

(100atm)

= 142mL

2 If 25 L of a gas at 1100 kPa is expanded to 40 L at constant temperature what will be the new value of pressure

P1V 1= P2V2

P1=1100 kPa P2= kPa

V1= 25 L V2= 40 L

P2=P1V1

V2

=(1100 kPa) ( 25 L)

(40 L)

= 69 kPa

Real World Application BOYLErsquoS LAW

bull Syringes and turkey basters are operated by Boyles Law pulling back on the plunger increases the volume inside the syringe which decreases the pressure which then corrects when liquid is drawn into the syringe thereby shrinking the volume again

bull Spray cans like spray paint and air freshener are governed by Boyles Law intense pressure inside the can pushes outward on the liquid inside the can trying to escape and forces the liquid out when the cap makes an opening

bull You breathe because of Boyles Law

bull Balloons work because of Boyles Law

bull A car (combustion) engine works when the sudden increase in pressure from the combustion of the fuel expands the cylinder and pushes on the piston causing the crankshaft to turn

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

1 A sample of oxygen gas has a volume of 1500mL at a pressure of 0947 atm What will the volume of the gas be at a pressure of 100 atm if the temperature remains constant

P1V 1= P2V2

P1= 0947 atm P2= 100 atmV1= 1500 mL V2= mL

V2=P1V1

P2

=(0947atm) (1500 mL)

(100atm)

= 142mL

2 If 25 L of a gas at 1100 kPa is expanded to 40 L at constant temperature what will be the new value of pressure

P1V 1= P2V2

P1=1100 kPa P2= kPa

V1= 25 L V2= 40 L

P2=P1V1

V2

=(1100 kPa) ( 25 L)

(40 L)

= 69 kPa

Real World Application BOYLErsquoS LAW

bull Syringes and turkey basters are operated by Boyles Law pulling back on the plunger increases the volume inside the syringe which decreases the pressure which then corrects when liquid is drawn into the syringe thereby shrinking the volume again

bull Spray cans like spray paint and air freshener are governed by Boyles Law intense pressure inside the can pushes outward on the liquid inside the can trying to escape and forces the liquid out when the cap makes an opening

bull You breathe because of Boyles Law

bull Balloons work because of Boyles Law

bull A car (combustion) engine works when the sudden increase in pressure from the combustion of the fuel expands the cylinder and pushes on the piston causing the crankshaft to turn

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

2 If 25 L of a gas at 1100 kPa is expanded to 40 L at constant temperature what will be the new value of pressure

P1V 1= P2V2

P1=1100 kPa P2= kPa

V1= 25 L V2= 40 L

P2=P1V1

V2

=(1100 kPa) ( 25 L)

(40 L)

= 69 kPa

Real World Application BOYLErsquoS LAW

bull Syringes and turkey basters are operated by Boyles Law pulling back on the plunger increases the volume inside the syringe which decreases the pressure which then corrects when liquid is drawn into the syringe thereby shrinking the volume again

bull Spray cans like spray paint and air freshener are governed by Boyles Law intense pressure inside the can pushes outward on the liquid inside the can trying to escape and forces the liquid out when the cap makes an opening

bull You breathe because of Boyles Law

bull Balloons work because of Boyles Law

bull A car (combustion) engine works when the sudden increase in pressure from the combustion of the fuel expands the cylinder and pushes on the piston causing the crankshaft to turn

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

Real World Application BOYLErsquoS LAW

bull Syringes and turkey basters are operated by Boyles Law pulling back on the plunger increases the volume inside the syringe which decreases the pressure which then corrects when liquid is drawn into the syringe thereby shrinking the volume again

bull Spray cans like spray paint and air freshener are governed by Boyles Law intense pressure inside the can pushes outward on the liquid inside the can trying to escape and forces the liquid out when the cap makes an opening

bull You breathe because of Boyles Law

bull Balloons work because of Boyles Law

bull A car (combustion) engine works when the sudden increase in pressure from the combustion of the fuel expands the cylinder and pushes on the piston causing the crankshaft to turn

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

Temeperature-Volume Relationship Charlersquos Law

bull Volume and temperature are proportional at constant pressure

bull (when gases are heated they expand)

bull temperature = volume (K)

bull temperature = Volume (K)

= kV

T

V1

T1

=V2

T2

KE of the gases volume temperature

Charless Law Calculation A balloon is inflated to 665 mL volume at 27degC It is immersed in a dry-ice bath at minus785degC What is its volume assuming the pressure remains constant

V1= 665 mL V2= mL

T1= 27degC + 273 K

= 300 K

T2= -785degC + 273 K

= 1945 K

V1

T1

=V2

T2

V1

T1

=V2T2 =

(665 mL)( 1945 K)

(300 K)

= 43 x 10^2 mL

1 Helium gas in a balloon occupies 25 L at 3000K The balloon is dipped into liquid nitrogen that is at a temperature of 800K What will be volume of the helium in the balloon at the lower temperature be

V1= 25 L

T1= 300 K T2= 800 K

V1

T1

=V2

T2

V1

T1

=V2 =(25 L)( 800 K)

(300 K)

= 067 L

V2= mL

T2

2 A helium filled balloon has a volume of 275 L at 200 degC The volume of the balloon changes to 246 L when placed outside on a cold day What is the temperature outside in degC

V1= 275 L

T1= 20 degC + 273 K = 293 K T2= degC

V1

T1

=V2

T2

V1

V2=T2 =(246 L)( 293 K )

(275 L)

= 26210 K = -1089 degC = -109 degC

V2= 246 L

T1

Real World Application CHARLErsquoS LAW

bull A balloon blown up inside a warm building will shrink when it is carried to a colder area like the outdoors

bull Humans lung capacity is reduced in colder weather runners and other athletes may find it harder to perform in cold weather for this reason

bull Charles Law along with a couple other gas laws is responsible for the rising of bread and other baked goods in the oven tiny pockets of air from yeast or other ingredients are heated and expand causing the dough to inflate which ultimately results in a lighter finished baked good

bull Car (combustion) engines work by this principle the heat from the combustion of the fuel causes the cylinder to expand which pushes the piston and turns the crankshaft

Temperature-Pressure Relationships Gay-Lussacrsquos Lawbull Pressure and temperature are proportional

at constant volume

bull pressure = temperature (K)

bull pressure = temperature (K)

= kP

T

P1

T1

=P2

T2

1 Helium gas in a balloon occupies 25 L at 3000K The balloon is dipped into liquid nitrogen that is at a temperature of 800K What will be volume of the helium in the balloon at the lower temperature be

V1= 25 L

T1= 300 K T2= 800 K

V1

T1

=V2

T2

V1

T1

=V2 =(25 L)( 800 K)

(300 K)

= 067 L

V2= mL

T2

2 A helium filled balloon has a volume of 275 L at 200 degC The volume of the balloon changes to 246 L when placed outside on a cold day What is the temperature outside in degC

V1= 275 L

T1= 20 degC + 273 K = 293 K T2= degC

V1

T1

=V2

T2

V1

V2=T2 =(246 L)( 293 K )

(275 L)

= 26210 K = -1089 degC = -109 degC

V2= 246 L

T1

Real World Application CHARLErsquoS LAW

bull A balloon blown up inside a warm building will shrink when it is carried to a colder area like the outdoors

bull Humans lung capacity is reduced in colder weather runners and other athletes may find it harder to perform in cold weather for this reason

bull Charles Law along with a couple other gas laws is responsible for the rising of bread and other baked goods in the oven tiny pockets of air from yeast or other ingredients are heated and expand causing the dough to inflate which ultimately results in a lighter finished baked good

bull Car (combustion) engines work by this principle the heat from the combustion of the fuel causes the cylinder to expand which pushes the piston and turns the crankshaft

Temperature-Pressure Relationships Gay-Lussacrsquos Lawbull Pressure and temperature are proportional

at constant volume

bull pressure = temperature (K)

bull pressure = temperature (K)

= kP

T

P1

T1

=P2

T2

2 A helium filled balloon has a volume of 275 L at 200 degC The volume of the balloon changes to 246 L when placed outside on a cold day What is the temperature outside in degC

V1= 275 L

T1= 20 degC + 273 K = 293 K T2= degC

V1

T1

=V2

T2

V1

V2=T2 =(246 L)( 293 K )

(275 L)

= 26210 K = -1089 degC = -109 degC

V2= 246 L

T1

Real World Application CHARLErsquoS LAW

bull A balloon blown up inside a warm building will shrink when it is carried to a colder area like the outdoors

bull Humans lung capacity is reduced in colder weather runners and other athletes may find it harder to perform in cold weather for this reason

bull Charles Law along with a couple other gas laws is responsible for the rising of bread and other baked goods in the oven tiny pockets of air from yeast or other ingredients are heated and expand causing the dough to inflate which ultimately results in a lighter finished baked good

bull Car (combustion) engines work by this principle the heat from the combustion of the fuel causes the cylinder to expand which pushes the piston and turns the crankshaft

Temperature-Pressure Relationships Gay-Lussacrsquos Lawbull Pressure and temperature are proportional

at constant volume

bull pressure = temperature (K)

bull pressure = temperature (K)

= kP

T

P1

T1

=P2

T2

Real World Application CHARLErsquoS LAW

bull A balloon blown up inside a warm building will shrink when it is carried to a colder area like the outdoors

bull Humans lung capacity is reduced in colder weather runners and other athletes may find it harder to perform in cold weather for this reason

bull Charles Law along with a couple other gas laws is responsible for the rising of bread and other baked goods in the oven tiny pockets of air from yeast or other ingredients are heated and expand causing the dough to inflate which ultimately results in a lighter finished baked good

bull Car (combustion) engines work by this principle the heat from the combustion of the fuel causes the cylinder to expand which pushes the piston and turns the crankshaft

Temperature-Pressure Relationships Gay-Lussacrsquos Lawbull Pressure and temperature are proportional

at constant volume

bull pressure = temperature (K)

bull pressure = temperature (K)

= kP

T

P1

T1

=P2

T2

Temperature-Pressure Relationships Gay-Lussacrsquos Lawbull Pressure and temperature are proportional

at constant volume

bull pressure = temperature (K)

bull pressure = temperature (K)

= kP

T

P1

T1

=P2

T2

Gay-Lussacrsquos Law Calculation1 An aerosol can containing gas at 101 kPaand 22degC is heated to 55degC Calculate the pressure in the heated can

P1= 101 kPa

T1= 22 degC + 273 K = 295 K T2= 55 degC + 273K = 328 K

P1

T1

=P2

T2

T1

P1=P2 =(101 kPa)( 328 K )

(295 K)

= 110 kPa

P2= kPa

T2

2 A sample of helium gas is at 122 kPa and 22degC Assuming constant volume What will the temperature be when the pressure is 203 kPa

P1= 122 kPa

T1= 22 degC + 273 K = 295 K T2= K

P1

T1

=P2

T2

P1

P2=T2 =(203 kPa)(295K)

(122 kPa)

= 490K or 220degC

P2= 203 kPa

T1

Real World Application GAY-LUSSACrsquoS LAW

bull Bullets and cannons are based on these principles gas super-heated by the burning of gun powder is trapped behind the bullet and expands until the bullet leaves the barrel

bull Someone opening an oven may feel a quick flow of hot air the air inside the oven is heated therefore pressurized The same is true when heating food in closed containers often a container will open to release the pressure If it does not opening the container will quickly release all the pent-up pressure which can be very dangerous because the gases inside the hot container may be super-heated This is why it is always best to open hot containers away from your body and face

Volume-Molar Relationships Avogadrorsquos Law

bull Volume and number of moles (n) areproportional at constant temperature and pressure

bull volume = number of moles

bull volume = number of moles

bull 224 L for 1 mole of a gas STP

= kVn

V1

n1

=V2

n2

Avogadrorsquos Lawbull What volume of CO2 contains the same

number of molecules as 200mL of O2 at the same conditions

20 mL

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

2 A sample of helium gas is at 122 kPa and 22degC Assuming constant volume What will the temperature be when the pressure is 203 kPa

P1= 122 kPa

T1= 22 degC + 273 K = 295 K T2= K

P1

T1

=P2

T2

P1

P2=T2 =(203 kPa)(295K)

(122 kPa)

= 490K or 220degC

P2= 203 kPa

T1

Real World Application GAY-LUSSACrsquoS LAW

bull Bullets and cannons are based on these principles gas super-heated by the burning of gun powder is trapped behind the bullet and expands until the bullet leaves the barrel

bull Someone opening an oven may feel a quick flow of hot air the air inside the oven is heated therefore pressurized The same is true when heating food in closed containers often a container will open to release the pressure If it does not opening the container will quickly release all the pent-up pressure which can be very dangerous because the gases inside the hot container may be super-heated This is why it is always best to open hot containers away from your body and face

Volume-Molar Relationships Avogadrorsquos Law

bull Volume and number of moles (n) areproportional at constant temperature and pressure

bull volume = number of moles

bull volume = number of moles

bull 224 L for 1 mole of a gas STP

= kVn

V1

n1

=V2

n2

Avogadrorsquos Lawbull What volume of CO2 contains the same

number of molecules as 200mL of O2 at the same conditions

20 mL

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Real World Application GAY-LUSSACrsquoS LAW

bull Bullets and cannons are based on these principles gas super-heated by the burning of gun powder is trapped behind the bullet and expands until the bullet leaves the barrel

bull Someone opening an oven may feel a quick flow of hot air the air inside the oven is heated therefore pressurized The same is true when heating food in closed containers often a container will open to release the pressure If it does not opening the container will quickly release all the pent-up pressure which can be very dangerous because the gases inside the hot container may be super-heated This is why it is always best to open hot containers away from your body and face

Volume-Molar Relationships Avogadrorsquos Law

bull Volume and number of moles (n) areproportional at constant temperature and pressure

bull volume = number of moles

bull volume = number of moles

bull 224 L for 1 mole of a gas STP

= kVn

V1

n1

=V2

n2

Avogadrorsquos Lawbull What volume of CO2 contains the same

number of molecules as 200mL of O2 at the same conditions

20 mL

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Volume-Molar Relationships Avogadrorsquos Law

bull Volume and number of moles (n) areproportional at constant temperature and pressure

bull volume = number of moles

bull volume = number of moles

bull 224 L for 1 mole of a gas STP

= kVn

V1

n1

=V2

n2

Avogadrorsquos Lawbull What volume of CO2 contains the same

number of molecules as 200mL of O2 at the same conditions

20 mL

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Avogadrorsquos Lawbull What volume of CO2 contains the same

number of molecules as 200mL of O2 at the same conditions

20 mL

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Real World Application AVOGADROrsquoS LAW

bull Avogadros Law along with other gas laws explains why bread and other baked goods rise Yeast or other leavening agents in the dough break down the long carbohydrates from the flour or sugar and convert them into carbon dioxide gas and ethanol The carbon dioxide forms bubbles and as the yeast continues to leaven the dough the increase in the number of particles of carbon dioxide increase the volume of the bubbles thereby puffing up the dough

bull Avogadros Law explains projectiles like cannons and guns the rapid reaction of the gunpowder very suddenly creates a large amount of gas particles--mostly carbon dioxide and nitrogen gases--which increase the volume of the space behind the cannon or bullet until the projectile has enough speed to leave the barrel

bull A balloon inflates because of Avogadros Law the person blowing into the balloon is inputing a lot of gas particles so the balloon increases in volume

bull We breathe because of Avogadros Law among others the lungs expand so more gas particles can enter the lungs from the outside air (inhaling) Then the lungs contract so the waste gas particles are expelled (exhaling)

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

The CombinedGas Law

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Combining the gas laws

Jacques CharlesRobert Boyle

P1V1 = P2V2V1

T1

=V2

T2

These are all subsets of a

more encompassing law

the combined gas law

P1

T1

=P2

T2

P1V1 P2V2

T1 T2

=

Joseph Louis Gay-Lussac

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Gas Laws

Combined Gas Law 2

22

1

11

T

VP

T

VP

The ratio of the product

of pressure and volume and

the temperature of a gas is equal to a constant

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Boylersquos Law

Charlersquos Law

Gay-Lussacrsquos Law

Avogadrorsquos Law

Ideal Gas

Molecular Composition of Gasesbull No gas perfectly obeys all four of these laws under

all conditions

bull These assumptions work well for most gases and most conditions

bull One way to model a gasrsquos behavior is to assume that the gas is an ideal gas that perfectly follows these laws

bull An ideal gas unlike a real gas

bull does not condense to a liquid at low temperatures

bull does not have forces of attraction or repulsion between the particles and is

bull Is composed of particles that have no volume

Ideal Gas Law

PV = nRTbull P = pressure in atmbull V = volume in litersbull n = molesbull R = proportionality constant

ndash= 00821 L atm molmiddotKbull T = temperature in Kelvins

The ideal gas law expresses the relationship between pressure volume and temperature of a fixed amount of gas

Ideal Gas Law CalculationHow many moles of gas are contained in

224 L liter at 100 atm and 283K

P = 100 atm

V = 224 L

n = Moles

R = 00821 Latmmol K

T = 283 K

PV = nRT

RT

PVn =

(00821 Latmmol K) ( 283 K)

(100 atm)(224L)=

=964 moles

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Ideal Gas

Molecular Composition of Gasesbull No gas perfectly obeys all four of these laws under

all conditions

bull These assumptions work well for most gases and most conditions

bull One way to model a gasrsquos behavior is to assume that the gas is an ideal gas that perfectly follows these laws

bull An ideal gas unlike a real gas

bull does not condense to a liquid at low temperatures

bull does not have forces of attraction or repulsion between the particles and is

bull Is composed of particles that have no volume

Ideal Gas Law

PV = nRTbull P = pressure in atmbull V = volume in litersbull n = molesbull R = proportionality constant

ndash= 00821 L atm molmiddotKbull T = temperature in Kelvins

The ideal gas law expresses the relationship between pressure volume and temperature of a fixed amount of gas

Ideal Gas Law CalculationHow many moles of gas are contained in

224 L liter at 100 atm and 283K

P = 100 atm

V = 224 L

n = Moles

R = 00821 Latmmol K

T = 283 K

PV = nRT

RT

PVn =

(00821 Latmmol K) ( 283 K)

(100 atm)(224L)=

=964 moles

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Molecular Composition of Gasesbull No gas perfectly obeys all four of these laws under

all conditions

bull These assumptions work well for most gases and most conditions

bull One way to model a gasrsquos behavior is to assume that the gas is an ideal gas that perfectly follows these laws

bull An ideal gas unlike a real gas

bull does not condense to a liquid at low temperatures

bull does not have forces of attraction or repulsion between the particles and is

bull Is composed of particles that have no volume

Ideal Gas Law

PV = nRTbull P = pressure in atmbull V = volume in litersbull n = molesbull R = proportionality constant

ndash= 00821 L atm molmiddotKbull T = temperature in Kelvins

The ideal gas law expresses the relationship between pressure volume and temperature of a fixed amount of gas

Ideal Gas Law CalculationHow many moles of gas are contained in

224 L liter at 100 atm and 283K

P = 100 atm

V = 224 L

n = Moles

R = 00821 Latmmol K

T = 283 K

PV = nRT

RT

PVn =

(00821 Latmmol K) ( 283 K)

(100 atm)(224L)=

=964 moles

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Ideal Gas Law

PV = nRTbull P = pressure in atmbull V = volume in litersbull n = molesbull R = proportionality constant

ndash= 00821 L atm molmiddotKbull T = temperature in Kelvins

The ideal gas law expresses the relationship between pressure volume and temperature of a fixed amount of gas

Ideal Gas Law CalculationHow many moles of gas are contained in

224 L liter at 100 atm and 283K

P = 100 atm

V = 224 L

n = Moles

R = 00821 Latmmol K

T = 283 K

PV = nRT

RT

PVn =

(00821 Latmmol K) ( 283 K)

(100 atm)(224L)=

=964 moles

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Ideal Gas Law CalculationHow many moles of gas are contained in

224 L liter at 100 atm and 283K

P = 100 atm

V = 224 L

n = Moles

R = 00821 Latmmol K

T = 283 K

PV = nRT

RT

PVn =

(00821 Latmmol K) ( 283 K)

(100 atm)(224L)=

=964 moles

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Calculate the pressure exerted by 43 mol of nitrogen in a 65L of cylinder at 50degC

P = atm V = 65 L

n = 43 mol R = 00821 Latmmol K

T = 5degC + 273K = 278 K

PV = nRTnRT

VP =

(43 mol)(00821 Latmmol K) ( 278 K)

(65 L)=

=15 atm

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

What will be the volume of 111 mol of nitrogen where the temperature is -57degC and pressure is 250 atm

P = 250 atm V = L

n = 111 mol R = 00821 Latmmol K

T = -57degC + 273K = 216 K

PV = nRTnRT

PV =

(111 mol)(00821 Latmmol K) ( 216 K)

(250 atm)=

=79 L

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Real World Application IDEAL GAS LAW

bull The Ideal Gas Law provides important information regarding reactions like the combination of gases stoichiometry like the gas produced in a reaction physical processes like the mixing of gases and thermodynamic processes like the movement of matter toward disorder

bull The Ideal Gas Law is used in engineering to determine the capacity of storage containers It is also helpful in determining the efficiency and standard operation of equipment

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Checking for understanding

1 Explain how is ideal gas different from a normal gas

2 Write the formula for ideal gas

3 What variables can be determined by using the formula

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Gas Behavior ndash DiffusionEffusion

bull Diffusion is the movement of particles from regions of higher density to regions of lower density

bull Effusion is the passage of gas particles through a small opening

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

bull Both effusion and difusssion depend on

the molar mass of the particle which determines the speed

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Effusion

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

bullDiffusiondescribes the mixing

of gases The rate of

diffusion is the rate

of gas mixing

bullMolecules move

from areas of high

concentration to low

concentration

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Effusion a gas escapes through a tiny hole in its container

-Think of a nail in your car tirehellip

Diffusion

and effusion

are

explained

by the next

gas law

Grahamrsquos

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Next slides not used 2015

bull Grahams law calculations

bull Daltonrsquos law

bull Ideal gas law

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Comparing distance traveled

You can compare the distanced traveled by 2 gases in the same amount of time using this equation also

Distance traveled by A = MassB

Distance traveled by B MassA

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Grahamrsquos Lawbull The molecular speeds vA and vB of gases A and

B can be compared according to Grahamrsquos law of diffusion shown below

bull Grahamrsquos law of diffusion states that the rate of diffusion of a gas is inversely proportional to the square root of the gasrsquos molar mass

bull Particles of low molar mass travel faster than heavier particles

A

B

B

A

M

M

r

r

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Grahamrsquos Law Calculation

bull At the same temperature which molecule travels faster O2 or H2

2

2

2

2

H

O

O

H

M

M

r

r

2

2

H

O

g 202

g 3200 = 398

Hydrogen travels 398 times faster than oxygen

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Grahamrsquos Law CalculationOxygen molecules have a rate of about 480 ms at room

temperature At the same temperature what is the rate of molecules of sulfur hexafluoride SF6

32g

146

r

480ms

6S

g

F

rO2 = 480 ms

rSF6= ms

MO2 = 32g

MSF6= 146g

2

6

6

2

O

S

S

O

M

M

r

r F

F

= 220 ms

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Daltonrsquos Lawbull The pressure of each gas in a mixture is called

the partial pressurebull The total pressure of a mixture of gases is the

sum of the partial pressures of the gases This principle is known as Daltonrsquos law of partial pressure

bull Ptotal = PA + PB + PC

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Daltonrsquos Law Calculation

bull What is the total pressure in a balloon filled with air (O2 amp N2) if the pressure of the oxygen is 170 mm Hg and the pressure of nitrogen is 620 mm Hg

bullPtotal = POxygen + Pnitrogen

bullPtotal = PA + PB + PChellip

= 170 mmHg + 620 mmHg

= 790 mmHg

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Real World Application DALTONrsquoS LAW

bull Daltons Law is especially important in atmospheric studies The atmosphere is made up principally of nitrogen oxygen carbon dioxide and water vapors the total atmospheric pressure is the sum of the partial pressures of each gas The different partial pressures account for a lot of the weather we experience

bull Daltons Law plays a large role in medicine and other breathing areas Different proportions of gas have different therapeutic effects so it is important to know the partial pressures of each gas in a gas line or gas tank for example

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Checking for understanding

State the law

Explain the law in your own words

Write the formula(s)

Grahamrsquos Law

Daltonrsquos Law

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Grahamrsquos Law

bull The rate of effusion and diffusion is

inversely proportional to the square root

of the molar mass of the molecules

bull Derived from Kinetic energy = 12 mv2

bull m = the molar mass and v = the

velocity

RateA MassB

RateB MassA

=

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

bull Sample compare rates of effusion of

Helium with Nitrogen ndash

bull With effusion and diffusion the type of

particle is important

ndash Gases of lower molar mass diffuse and

effuse faster than gases of higher molar

mass

bull Helium effuses and diffuses faster than

nitrogen ndash thus helium escapes from a

balloon quicker than many other gases

Grahamrsquos Law

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves

Big Points to Remember

bull All gases at the same temperature have the same average kinetic energy

bull But they do not have the same average velocity (or speed)

bull Speed depends on Molar Mass

bull The heavier the gas the slower it moves

bull The lighter the gas the faster it moves