A phase change is the reversible physical change that takes place when a substance changes from one state to another

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Types of phase changes

Freezing - liquid to solid

Melting - solid to liquid

Vaporization (boiling) - liquid to gas 

Condenstion- gas to liquid 

Sublimation- solid to gas

Depostion- gas to solid

 

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The tempature during a phase change remains constant (doesnt change) 

During a phase change it is either

• absorbing energy

             -OR-

• releasing energy 

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Endothermic: Internal heat (adding heat/energy)

-ex. Melting ice cubes, Boiling water 

Exothermic: External heat (removing heat/energy)

-ex. freezing ice cubs, burning sugar 

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VAPORIZATION

 

Evaporation

- Vaporization is the phase change

- at the surface of a liquid

- below the boiling point of a liquid (takes longer)

Boiling 

- Vaporization is the phase change

- throughout the liquid

- at the boilding point of a liquid (quicker)