Classification of Matter-Today’s Words
– Matter
– Solid
– Liquid
– Gas
– Surface tension
– Viscosity
Today’s Special Words
– Crystalline solids
– Amorphous solids
– Compressibility
Classification of Matter
Matter is anything that has mass and occupies space.
We can classify matter based on whether it’s solid, liquid, or gas.
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Classifying Matterby Physical State
Matter can be classified as solid, liquid, or gas based on the characteristics it exhibits.
• fixed = keeps shape when placed in a container • indefinite = takes the shape of the container
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Solids
Have definite shape and definite volume
Particles are tightly packed– though they may vibrate
The close packing of the particles results in solids being incompressible.– Solid particles vibrating
– What is water? Solids vs liquids
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Crystalline Solids
Some solids have their particles arranged in an orderly geometric pattern─we call these crystalline solids.– salt – diamonds– sugar
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Amorphous Solids
Some solids have their particles randomly distributed without any long-range pattern─we call these amorphous solids.– plastic– glass– charcoal
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Liquids
Do not have definite shape but do have definite volume
Particles are loosely packedThe close packing results in
liquids being incompressible.
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Liquids
Viscosity Flows slower than water Slows down a temperature
goes down Examples:
– Cooking Oil
– Car Oil
– Syrup
– Lava
Surface Tension Seen with water Molecules are attracted to
each other Example:
– Water drops on grass
– Bug walking across pond
– Over filling a glass
States of Matter
https://www.youtube.com/watch?v=nrUBPO6zZ40&list=PLED25F943F8D6081C
http://labs.minutelabs.io/Brownian-Motion/
https://www.youtube.com/watch?v=-QhU8eMR4IQ
Gases
In the gas state, the particles have complete freedom from each other.
The particles are constantly flying around, bumping into each other and the container.
In the gas state, there is a lot of empty space between the particles.– on average
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Gases
Because there is a lot of empty space, the particles can be squeezed closer together; therefore, gases are compressible.
Because the particles are not held in close contact and are moving freely, gases expand to fill and take the shape of their container, and will flow.
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11 Vapor
Matter that exists in the gas state but is generally a liquid or solid at room temperature is called vapor.
Water, for example, is a liquid at room temperature. Thus, water vapor is the term for the gas state of water.
Definite ShapeDefinite Volume
AtomsMatter
No definite shape
No definite volume
Particles close together
Particles slide past each other
Particles move quickly
Thermal Energy
Lecture 3.2a
Heat and Thermal Energy
Thermal Energy is Thermal Energy is the energy that moves the energy that moves in heat transferin heat transfer
Lower temp = lower thermal energy Lower temp = lower thermal energy
Higher temp = higher Higher temp = higher thermal energy thermal energy
Temperature
Temperature:
– A measure of the average kinetic energy of the particles in an object
What Changes Thermal Energy?
1. Temperature1. Temperature
2. 2. Amount of substance Amount of substance More moving particles = more thermal energyMore moving particles = more thermal energy
What Is Heat? What Is Heat?
The transfer of The transfer of energyenergy between objects at between objects at different temperatures different temperatures
High Temperature High Temperature Objects Objects
Low Temperature Objects Low Temperature Objects
** Energy ** Energy moves from moves from high-temp. high-temp.
to low-tempto low-temp.
Kinetic Energy of molecules!!Kinetic Energy of molecules!!
Thermal Energy is Related Thermal Energy is Related To…?To…?
Reaching The Same Temperature
The point at which The point at which both objects in contact both objects in contact reach the same reach the same temperature…temperature…
** ** NO CHANGENO CHANGE IN THERMAL IN THERMAL ENERGY OCCURS!!ENERGY OCCURS!!
Changes of State
Section 2b
Changes of State
There are six major changes of state•Freezing•Melting•Vaporization •Evaporation•Condensation•Sublimation
Freezing
Freezing – The change of state from a liquid to a solid.
As liquids cool their particles begin to slow, bringing them closer together
The freezing point of water is 0oC
Freezing is a loss of thermal energy
Melting
Melting – The change of state from a solid to a liquid.
As a substance absorbs heat energy the objects particles begin to heat up and move faster and farther away from one another.
The melting point of water is 0oCMelting is a gain of thermal energy.
Vaporization
Vaporization – Process that occurs when a liquid becomes a gas known as boiling
Dependent on how strongly the particles in the object are held together.
The boiling point of water is 100oCVaoprization is a gain of thermal energy.
Evaporation
Evaporation – Occurs when a liquid acquires enough energy to become a gas only on the surface of a liquid.
Evaporation is a gain of thermal energy.
Condensation
Condensation – Occurs when a gas loses enough thermal energy to become a liquid.
Particles in a gas lose energy and begin to move slower, coming closer together.
Condensation is a loss of thermal energy.
Sublimation
Sublimation – Occurs when the surface particles of a solid gain enough energy to become a gas.
The object goes directly from a solid to a gas skipping the liquid phase. Ex. Dry Ice
Sublimation is a gain of thermal energy.
Vaporization
Definite ShapeDefinite Volume
AtomsMatter
No definite shape
No definite volume
Particles close together
Particles slide past each other
Particles move quickly
Sublimation
Melting/Freezing
Evaporation
Vaporization
Condensation
Phase Change
What happens when things melt, boil, etc.?During a phase change, Thermal energy is
either absorbed or released.
– Solid to a Liquid and a Liquid to a Gas both Absorb Thermal Energy.
– Gas to a Liquid and Liquid to a Solid both Release Thermal Energy.
Phase Change
What happens to substances when they are heated or cooled?
When objects are heated they Expand. When objects are cooled the Contract.
– Water is the only exception. It actually expands as it cools.
Phase Change
Change of State Graph