Chemistry12ReactionKineticsI
Name:Date:Block:
1. CalculatingRates2. MeasuringRates3. FactorsAffectingRates
MonitoringandCalculatingReactionRatesReactionRate=Timeunits: RateUnits:Giventhefollowingequationanddata:
2HNO3(aq)+Cu(s)→NO2(g)+H2O(l)+CuNO3(aq)
Massofcopper(g)
3.26 2.93 2.60
Time(min) 5.00 7.00 9.00
a) Doesthereactionabovehaveaconstantrate?Explainwhyorwhynot.
b) Calculatetherateinunitsof(gCu/min).
c) Calculatetherateinunitsof(moleCu/min).
d) CalculatetherateinmolesHNO3consumedperminute(rememberthemoleratio).
e) Calculatetherateinunitsof(g/min)forHNO3.
changeimeasurabequanh.lychangein time
seconds min gls Llmin etchours
mass of CuW 0.33g
Rate Smog 2.60g3.26gst.me9comin 5comin 497 017gCumin
0 lt uxlmolCu 2.7x103molCuminmin 63.5g
2.7 103 014 x 2n N0z 5.4 103 MolHNozyminmin ImdCu
5.4 103motHNOz 63.0 O34gHN031miamin lmotHN03
Considerthefollowinggraph:
1. IsAareactantoraproduct?Explainyouranswer.
2. Determinethereactionrateat40.secondsand100.seconds.
3. Explainthetrendobservedintermsofreactionkinetics.
product time 0 CA7 0Mas rain progresses A is produced
40 s 100 s
0.61 10.07 477 10.0107740s
rxn slowingdownnot constant ratereactant isbeingusedupandlessproductisbeing produced
MeasuringReactionRatesChangingratesofreactionscanbefoundbymeasuringachangeinoneofthefollowingproperties:
1. Colour
2. Temperature
3. Pressure
4. MassStatefivedifferentmethodsformeasuringtherateofthereactionofanironnailinconcentratedhydrochloricacid:
a. Whatisthebalancedchemicalequation?(HCliscolourless;FeCl2isyellow-orange)
b. Whatpropertieswould/couldyoumonitor?
Δ[HCl]time
ΔpHtime
ΔVolH2time
ΔPH2time
ΔmassH2time
Titrate pHmeter Eudimeter Manometer Balance
M/s pHunits/s mL/s kPa/s g/s
CompleteReactionRatesWorksheet
scolourintensity 5 Amls timeA time
SC s k 6SMStime DtimeSatin AkPa 7 SpitAtime D time
slime
Fees t 2Hchaq Feckcag t H2cgcolourless yellow orange
1 colourintensity yelloworange 5 pH 9morebasic2 Vol Hey 9 6 pressure Hug 93 mass Fees L 7 CHU d4 temp
FactorsAffectingReactionRates
“Whenthe…increases,thentherate….”Reactionratesareaffectedbythefollowingfactors:
1. Temperature• Whenthetemperatureisincreased,theparticleshave_____________________energy.• Willresultinmorefrequentandmoreforcefulcollisions.• Thetimeforthereactiontotakeplacewill__________________thereforethereactionratewill
________________.2. Concentration
• Asthereactantconcentrationincreases,therearemoreparticlestocollidewitheachother.• Thereactionratewill______________________.
3. Pressure• Anincreaseinpressurecausestheparticlestobe_______________together.• Pressureisinverselyproportionalto___________________________.
o Anincreaseinpressureresultsina____________________ofvolumeandviceversa.
4. SurfaceArea/Phase• Withagreaterthesurfaceareaexposed,thereisanincreaseinlocationswherethereaction
cantakeplace• Ex:
• Allowsfor______________________inreactionrate.
increased
decreaseincrease
increaseo T CT o o can 9 C T of
o o j aqueous solutionso o o and gasesvolume gas closer
volumedecrease
o O
lesso o LconcentIV TP Ndp
o oO o
solid Tmore Concentrated
increase
5. Natureofthereactants
• Factorssuchasionizationenergy,electronegativity,ionicandmolecularpolarity,size,complexityofstructure,etc.
• Ingeneral,atroomtemperaturetherateofaqueous>gas>liquid>solid.6. Presenceofacatalyst
• Substancesthatincreasetheratesofchemicalreactionswithoutbeingusedup.• (Aninhibitorisaspeciesthatreducestherateofachemicalreactionbycombiningwitha
reactanttostopitfromreactinginitsusualway.)
Thefollowingreactionistakingplaceataveryslowrateinaclosedcontaineratroomtemperature:
S(s)+O2(g)àSO2(g)Statewhateffecteachofthefollowingprocedureswillhaveontherateofthisreaction,andexplainwhytheprocedurehasthestatedeffect.
a) Thetemperatureisdecreased.
b) MoreO2(g)isaddedinthesamevolume.
c) Thesulphurisgroundupintoapowder.
d) Thevolumeofthecontainerisincreased.
BecarefulwhendiscussingMEASURINGreactionratesandAFFECTINGreactionrates.Reaction1:A(s)+B(aq)àC(aq)+D(g)
• Listtwowaysthereactionratecouldbemeasured:
• Listtwowaysthereactionrateabovecouldbeincreased:Reaction2:E(aq)+F(aq)àG(aq)+H(s)
• Listtwowaysthereactionratecouldbemeasured:
• Listtwowaysthereactionrateabovecouldbedecreased:
rain rate dparticlesslowdown lesschance of asuccessfulcollisionrim rate rmore Ozmolecules available for successfulrxn rate Tincreased location where r n can take
placerxn rate dlower frequency of successful collisions
vol Dg T pressureDog 9mass Acs dlook reactantsTSA Acs catalyst
Hemp r CB
mass H S fVol ofsystem d formation of
precipitated tempinhibitord CET and DCF