物理化學2期中試卷2009級

化學化工學院化學系2009年級化學/化生(10202分1- 1- m1- m m時其S$/J·K-1·mol-1m(A)- (B)- (C)- (D)-1- 1-5.CH2ICOOH+SCN-CH2(SCN)COOH+I-kIIkIkIk D+Bmole-1·cm3·s-1kNmol-1·dm3·s-1kc，kc 1-7.(A)單重態(tài)到三重態(tài)的躍 (B)三重態(tài)向基態(tài)的躍(C)振動模式不 (D)核自旋躍(A)不一 1-9.基元反應(yīng)A+B-C→A-B+C 的摩爾反應(yīng)焓rHm<0，B-C鍵的鍵能為BC，A為自由基，則反應(yīng)活化能等于：(A)0.300.05(C)0.05BC+0.05BC-1-

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(A) (B)(C) (D)二、計算題(共4題5010Forareversiblefirst—orderkkkBk1=10-2s-1and[B]eq/[A]eq=4.IfcA,0=0.01mol·dm-3andcB,0=0,whatwillbetheconcentrationofbeBafter30s?Tworadioactiveisotopesofphosphorushavehalf-livesthatmakethemusefulforscientificexperiments.32Phasahalf-lifeof14.3daysand33Phasahalf-lifeof25.3days.Bothradioisotopesofphosphorous,32Pand33P,arebetaemitters.Duringshieldingofβ-emissionfrom32P,X-rayphotonsofλ=0.1175nmareCalculatetheenergyofX-rayphotonsindecreasesto4569.7Ci（1Ci=3.7×1010s-1）after14.3days,calculatethe[32P]/[33P]ratioinitiallypresentinthesample.4.4.20ThegasphaseA2(g)+2

isacceleratedbycatalystC.Theoverallrateconstantisfoundtoincreaselinearlywiththecatalystconcentration.Followingmeasurementsaredoneat400Kwith[C]=0.050mol·dm-3Experiment[A2](mol·dm-[B](mol·dm-Initialrate(mol·dm-3·s-123WhatistheratelawofthisCalculatethenumericalvalueofkappat400Forthishypotheticalreactionfollowingmechanismwas 2A(g)+B(g)+C(g)

slowABC(g)

AB(g)+CheckthatthesuggestedmechanismgivestheequationfortheoverallCalculatethedissociationenthalpyofA2bondusingthefollowing·At400K,when[A2]is1.0×10-1mol·dm-3,[A]is4.0×10-3mol·dm-·Whenthefirstexperimentisrepeatedat425K,theinitialreactionrateincreasestoathree-foldvalue.·Activationenergyofthesloweststepis45.010NH2SO2OH363Kk1.16×10-3m3·mol-1·s-1Ea127.6kJ·mol-1mm

、≠H

、≠S$mm已知：玻耳常數(shù)kB=1.3806×10-23J·K-1,常數(shù)h=