Changes of State

Changes of State

◍ When matter transforms from one state to another

◍ Caused by adding or removing kinetic energy◌ Changes the temperature (average kinetic

energy of particles) ◍ Raise temperature à more kinetic energy à

particles move faster & take up more space◍ Lower temperature à less kinetic energy à

particles move slower & take up less space

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Changes of State

SOLID LIQUID

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Melting

Freezing

Melting point: the temperature where a

substance changes between solid and liquid

energy

energy

Changes of State

LIQUID GAS

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Evaporation

Condensation

Boiling point: the temperature where a

substance changes between liquid and gas

energy

energy

Changes of State

SOLID GAS

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Sublimation

Deposition

energy

energy

Changes of State

◍ 1. What is the melting point of water?

◍ 2. What is the boiling point of water?

◍ 3. What is the freezing point of water?

◍ 4. What is the condensation point of water?

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0ºC

100ºC

0ºC

100ºC

Physical Changes & Properties

Explained by KMT

Diffusion

◍ Movement of one material through another◍ Particles in motion move from high

concentration to low concentration◍ Ex: why you can smell cookies baking in a

different room

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Dice Demo

◍ 1 = forward◍ 2 = backwards◍ 3 = left◍ 4 = right◍ 5 = up (don’t move)◍ 6 = down (don’t move)

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Thermal Expansion & Contraction

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Thermal Expansion & Contraction

◍ Thermal Expansion – When Temperature Increases◌ Energy is added◌ Particles speed increases◌ Particles move farther apart◌ Particles occupy a larger volume

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Thermal Expansion & Contraction

◍ Thermal Contraction – When Temperature Decreases◌ Energy is removed◌ Particles speed decreases◌ Particles move closer together◌ Particles occupy a smaller volume

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