Phase Changes What did one water molecule say to another water molecule about vapor? Don’t worry it’s just a phase he’ll cool down.

Characteristics of Phase Changes States of matter are also referred to as phases. Phase Change: _______________________________ ____________________________________________ ____________________________________________ ____________________________________________

PHASE CHANGES Description of Phase Change Term for Phase Change Heat Movement During Phase Change_________ ___________ Heat ________ _________the solid as it melts. _________ ____________ Heat _______ the liquid as it freezes.

Description of Phase Change Term for Phase Change Heat Movement During Phase Change _____________ ________________ Heat _________ __________the liquid as it vaporizes. _____________ ________________ Heat ___________ the gas as it condenses. PHASE CHANGES

Description of Phase Change Term for Phase Change Heat Movement During Phase Change_____________ _______________ Heat ____________ the solid as it sublimates. _____________ ________________ Heat ________ the gas as it deposits.

Phase Change graphic __________________________ _________________ _______________

ENERGY AND CHANGES OF STATE The _____________________________ _________________________________. If energy is _________ to a substance its particles move _______. If energy is __________, its particles move _______.

__________________________________________ ________________________________________ ________________________________________. Steam has a higher temperature than liquid water, so particles in steam have more energy. Solid to Liquid - the particles in the liquid have ______________________________________ Steam to a liquid - the particles in the liquid have ______________________________________ Liquid to a solid - the particles in the solid have ______________________________________

Endothermic vs. Exothermic _____________________________________ ____________________________________. This is called an _________________ PROCESS. _____________________________________ _____________________________________. This is an _____________________ PROCESS.

Which are endothermic and which are exothemic? Liquid to a solid - _____________ ____________________-condensation Solid to a liquid - _____________ ___________________– sublimation Liquid to a gas – _________________ ______________________-deposition

Endothermic Exothermic

Average Kinetic Energy = Temperature ______________________ ______________________ ______________________ ______________________ ______________________

Using Temperature to Indicate Phase Change ____________________ ____________________ ____________________ ____________________ ____________________

Heat (thermal energy) Temperature º C A B C D E melting freezing condensing boiling Water Phase Change Graph ons/waterphases/status_water.htm

B C A F ED

Between E and F -Heat change in _________________ -Particles ______________________ -Temp. ________________________ -Gas Between D and E -Heat change in _________________ -Particles get ___________________ -Temp. ________________________ - Boiling Between B and C -Heat change in Potential Energy -Particles ___________________ -Temp. _____________________ - MELTING Between C and D -Heat change in ______________ -Particles ___________________ -Temp. ___________________ -liquid Between A and B -Heat change in _____________ -Particles move ______________ -Temp._____________________ -Solid