Chapter 8

States of Matter Standards

• Three Common States of Matter and their characteristics.
• Particle arrangement and behavior in a solid, liquid and gas.

3. How matter changes from one state to another.

- are the physical forms in which a substance can exist.

States of Matter

Remember:

Matter is made up of tiny particles called atoms and molecules.

Particles of Matter ……….

• Atoms and molecules are always in motion and bumping into each other.

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• The way particles interact with each other helps determine the state of the matter.

Particles of Matter

What makes a solid a solid?

A liquid a liquid?

Or a gas a gas?

States of Matter

States of Matter

A Solid – is the state of matter that has a definite shape and volume.

Solid

Particles in a solid….

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• Don’t move fast enough to overcome the strong attraction between them.

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2. Vibrate in place.

States of Matter

Solid

A Liquid is that state of matter that has a definite volume but takes the shape of its container.

Liquid

Particles in a Liquid ……..

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• Move fast enough to overcome some of the attraction between particles.

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• Close together but can slide past one another.

Liquids

Surface Tension Viscosity

Is a force that acts on the particles at the surface of a liquid.

Is a liquid’s resistance to flow.

Honey – high viscosity

Water – low viscosity

States of Matter

Solid

Liquid

Gas is the state of matter that has no definite shape or volume.

Gas

Particles in a Gas ……….

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• Move fast, overcome the attraction between particles.

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• Particles are far apart and move independently of one another.

• A Change of State is the change of a substance from one Physical form to another.

All Changes of State are Physical Changes!

What must happen to particles before they can change from one state to another?

The particles must gain or lose energy.

Endothermic – energy is gained or added during the change of state.

Five Changes of State

Endothermic

Sublimation - matter changes from a solid state directly to a gas state.

Endothermic – energy is absorbed.

Five Changes of State

Endothermic

Endothermic

Melting

Endothermic - Energy is absorbed.

Five Changes of State

Endothermic

Endothermic

Endothermic

Is the change of state from the liquid state to the gas state.

Endothermic – energy is absorbed.

Evaporation -

Exothermic – energy is lost or removed during the change of state.

Five Changes of State

Exothermic

Five Changes of State

Exothermic

Exothermic - Energy is released or lost.

Freezing – is the change of state from a liquid to a solid.

Five Changes of State

Exothermic

Exothermic

Exothermic – energy is lost.

What happens to the temperature of a substance as it changes state?

As a substance changes state, its temperature remains constant (doesn’t change) until the change of state is complete.