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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