States of Matter Changes

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October 01, 2018

Melting: From Solid to LiquidMelting: change from solid to liquid

Melting Point: temperature at which solid melts

­ Increase thermal energy (endothermic

Ex. Melting point of pure water is 0oC.

change)­ Thermal energy makes water molecules vibrate faster, raising their temperature.

­ At melting point, solid particles vibrate so fast they break free from their fixed positions.

Freezing: change from liquid to solid

Freezing Point: temperature at which liquid freezes

Freezing: From Liquid to Solid

Particles are moving so slowly they form regular patterns.

­ decrease in thermal energy (exothermicchange)

Vaporization: From Liquid to GasVaporization: change from a liquid to a gas

Boiling Point: temperature at which liquid turns to gas

***Note: Evaporation can occur at surface of

(Ex. Eventually a cup of water will evaporate liquid without heating liquid***

if left unattended; puddle of water after it rained)

Evaporation is the process when vaporization takes place.

Condensation: From Gas to LiquidCondensation: change from a gas to a liquid

Occurs when particles in a gas lose thermal energy to form a liquid (exothermic change).

Ex. ­ Clouds form when water vapor in atmosphere condenses into liquid droplets (rain)­ Bathroom mirror­ Sweat on a bottle

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