The MoleThe Mole

What is a mole?What is a mole?

A conversion factor we use in chemistry to make it easier to talk about a very large amount of particles of elements or compounds

1 dozen bagels = 12 bagels 1 mole bagels = 6.02 x 1023 bagels

A conversion factor we use in chemistry to make it easier to talk about a very large amount of particles of elements or compounds

1 dozen bagels = 12 bagels 1 mole bagels = 6.02 x 1023 bagels

Avogadro’s NumberAvogadro’s Number

Avogadro’s # = 6.02 x 1023 units

How does this number relate to a mole?

1 mole = 6.02 x 1023 units

*Units can be anything but in chemistry these units are referred to as: Particles Atoms Molecules Formula Units

Avogadro’s # = 6.02 x 1023 units

How does this number relate to a mole?

1 mole = 6.02 x 1023 units

*Units can be anything but in chemistry these units are referred to as: Particles Atoms Molecules Formula Units

How big is 6.02 x 1023?How big is 6.02 x 1023?

Astronomers estimate that there is a mole of stars in the Universe.

One mole of high school textbooks would cover the USA to a depth of about 300 Km.

One mole of marshmallows would cover the USA to a depth of 105 000 Km.

One mole of moles placed to head to tail would stretch 11 million light years and weigh 9/10 as much of the moon.

One mole of pennies would make at least seven stacks that would reach the moon.

One mole of watermelon seeds would be found inside a melon slightly larger than the moon.

Astronomers estimate that there is a mole of stars in the Universe.

One mole of high school textbooks would cover the USA to a depth of about 300 Km.

One mole of marshmallows would cover the USA to a depth of 105 000 Km.

One mole of moles placed to head to tail would stretch 11 million light years and weigh 9/10 as much of the moon.

One mole of pennies would make at least seven stacks that would reach the moon.

One mole of watermelon seeds would be found inside a melon slightly larger than the moon.

ExamplesExamples

1 mole Fe = 6.02 x 1023 atoms Fe

1 mole C12H22O11 = 6.02 x 1023 molecules C12H22O11

1 mole Al = 6.02 x 1023 atoms Al

1 mole BeF2 = 6.02 x 1023 formula units BeF2

1 mole Fe = 6.02 x 1023 atoms Fe

1 mole C12H22O11 = 6.02 x 1023 molecules C12H22O11

1 mole Al = 6.02 x 1023 atoms Al

1 mole BeF2 = 6.02 x 1023 formula units BeF2

How is the mole measured in the lab?

How is the mole measured in the lab?

It is impossible to count up individual particles of chemicals in the lab because of their small size

We must find another way to measure 6.02 x 1023 particles of a substance

It is impossible to count up individual particles of chemicals in the lab because of their small size

We must find another way to measure 6.02 x 1023 particles of a substance

How does mass relate to the mole?

How does mass relate to the mole?

What does an amu (atomic mass unit) measure?

1 amu = 1.66053886 × 10-27 kilograms

A relative scale used to measure the mass of single elements or compounds

What does an amu (atomic mass unit) measure?

1 amu = 1.66053886 × 10-27 kilograms

A relative scale used to measure the mass of single elements or compounds

Learning the termonology…Atomic Mass

Learning the termonology…Atomic Mass

Atomic Mass - measures the mass of a single atom in amu’s

Example: 1 atom Fe = 55.85 amu *Always go to the hundredths place when

taking measurements from the periodic table

Atomic Mass - measures the mass of a single atom in amu’s

Example: 1 atom Fe = 55.85 amu *Always go to the hundredths place when

taking measurements from the periodic table

Formula MassFormula Mass

Formula Mass - measures the mass of a single formula unit (ionic compound) in amu’s

Example: 1 formula unit BeF2 = 1Be 9.01 amu +2F 2(19.00 amu) = 47.01 amu

Formula Mass - measures the mass of a single formula unit (ionic compound) in amu’s

Example: 1 formula unit BeF2 = 1Be 9.01 amu +2F 2(19.00 amu) = 47.01 amu

Molecular MassMolecular Mass

Molecular Mass - measures the mass of a single molecule in amu’s

Example: 1 molecule C12H22O11 =

12 C atoms 12(12.01 amu) +

22 H atoms 22(1.01 amu) +

11 O atoms 11(16.00 amu) = 342.34 amu

Molecular Mass - measures the mass of a single molecule in amu’s

Example: 1 molecule C12H22O11 =

12 C atoms 12(12.01 amu) +

22 H atoms 22(1.01 amu) +

11 O atoms 11(16.00 amu) = 342.34 amu

Molar MassMolar Mass

The mass of 1 mole of any substance in grams Example:

1 atom Fe = 55.85 amu

1 mole (6.02 x 1023 atoms) Fe = 55.85 g

1 molecule C12H22O11 = 342.34 amu

1 mole (6.02 x 1023 molecules) C12H22O11 = 342.34 g

The mass of 1 mole of any substance in grams Example:

1 atom Fe = 55.85 amu

1 mole (6.02 x 1023 atoms) Fe = 55.85 g

1 molecule C12H22O11 = 342.34 amu

1 mole (6.02 x 1023 molecules) C12H22O11 = 342.34 g

What is a representative particle?What is a representative particle?

The smallest particle that represents the true identity of the entire substance without altering it’s characteristics or properties

Example: What is the representative particle of 52 Al atoms?

The smallest particle that represents the true identity of the entire substance without altering it’s characteristics or properties

Example: What is the representative particle of 52 Al atoms?

Answer: 1 atom Al

Example: What is the representative particle of 1 molecule of BeF2?

Answer: 1 atom Al

Example: What is the representative particle of 1 molecule of BeF2?

Answer: 1 molecule BeF2

1 atom of Be or 1 atom of F would not truly represent the properties and characteristics of BeF2

Answer: 1 molecule BeF2

1 atom of Be or 1 atom of F would not truly represent the properties and characteristics of BeF2