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