AP_Physics_B_-_Gas_Laws.ppt

GasLaws APPhysicsB ThePeriodicTable Alloftheelementsontheperiodictablearereferredtointermsoftheiratomicmass Thesymboluisdenotedasanatomicmassunit Atomic ofprotonsORelectrons AtomicMass ofprotons Neutrons 1amu 1 66x10 27kg TheMole Theword mole isderivedfromLatintomean heap or pile Itisbasicallyachemicalcountingunit Below whatwehaveiscalledtheMoleRoadMapanditsummarizeswhatamoleequals 1MOLE AtomicMassfromP T Avogadro s 6 02x1023Particles 22 4Litersgas STP STP StandardTemperatureandPressureST 0degreesCelsiusor273KelvinSP atmosphericpressure Example AflexiblecontainerofOxygen O2 hasavolumeof10 0m3atSTP Findthe molesandmoleculesthatexistinthecontainer 14 285 71moles 8 51x1029particles FactorsthateffectaGAS Thequantityofagas n inmolesThetemperatureofagas T inKelvin Celsiusdegrees 273 Thepressureofagas P inpascalsThevolumeofagas V incubicmeters GasLaw 1 Boyles Law completeTREEMAP Thepressureofagasisinverserelatedtothevolume MolesandTemperatureareconstant GasLaw 2 Charles Law Thevolumeofagasisdirectlyrelatedtothetemperature PressureandMolesareconstant GasLaw 3 Gay Lussac sLaw Thepressureofagasisdirectlyrelatedtothetemperature MolesandVolumeareconstant GasLaw 4 Avogadro sLaw Thevolumeofagasisdirectlyrelatedtothe ofmolesofagas PressureandTemperatureareconstant GasLaw 5 TheCombinedGasLaw YoubasicallytakeBoyle sCharles andGay Lussac sLawandcombinethemtogether Molesareconstant Example Pureheliumgasisadmittedintoaleakproofcylindercontainingamovablepiston Theinitialvolume pressure andtemperatureofthegasare15L 2 0atm and300K Ifthevolumeisdecreasedto12Landthepressureincreasedto3 5atm findthefinaltemperatureofthegas 420K GasLaw 6 TheIDEALGasLaw Allfactorscontribute Inthepreviousexamples theconstant k representedaspecificfactor s thatwereconstant ThatisNOTthecasehere soweneedaNEWconstant Thisiscalled R theuniversalgasconstant Example Aheliumpartyballoon assumedtobeaperfectsphere hasaradiusof18 0cm Atroomtemperature 20C itsinternalpressureis1 05atm Findthenumberofmolesofhelium