高三真題試卷化學(xué)答案1 sms

UNIVERSITYOFCAMBRIDGEINTERNATIONALMARKSCHEMEfortheMay/June2011questionpaperfortheguidanceofteachersThismarkschemeispublishedasanaidtoteachersandcandidates,toindicatetherequirementsoftheexamination.ItshowsthebasisonwhichExaminerswereinstructedtoawardmarks.ItdoesnotindicatethedetailsofthediscussionsthattookceatanExaminers’meetingbeforemarkingbegan,whichwouldhaveconsideredtheacceptabilityofalternativeanswers.Markschemesmustbereadinconjunctionwiththequestionpapersandthereportonthe CambridgeispublishingthemarkschemesfortheMay/June2011questionpapersformostIGCSE,GCEAdvancedLevelandAdvancedSubsidiaryLevelsyllabusesandsomeOrdinaryLevelsyllabuses. (a)N≡Ntriplebondis(very)ortheN2moleculehasno 3Mg(s)→ ?H1=3×148+3×2186=N2(g)→2N3 ?H2=994+2×2148=LE=–?H1–?H2–461=–12,753(kJmol Li3N+3H2O→NH3+3LiOH(balanced () disadvantage:LorLiwouldneedtobe (i)Li3N:100×14/35=40% urea:100×28/60=47% () ( NH2CONH2+H2O→2NH3+or→NH2CO2H+orNH2CONH2+2H2O→2NH3+ (iv)TheLiOHwouldbestronglyorwouldreasethepHofthe [Total: (a) hatcangoineither ()bothforward&reversereactionsaregoingonatthesametime,buttheconcentrationsofallspeciesdonotchange(owtte)orrateofforward=rateofbackward (i)Kc=[H+][OH ()Kw=[H+][OHrearrangementofequationin(i)givesKc[H2O]=[H+][OH]&Kw=Kc[H2O]orthe[H2O]iscontainedwithin

(i)Kwwillbehigherinhotwaterbecausereactionis (i)[OH]=5×102;[H+]=(1×1014)/5×102=2×pH=–log10[H+]= (correctans=

ecf4()[NH+]=[OH](= 4x2=1.8×105×0.05?x(=[OH])=9.49×10–4(moldm (correctans=[2])([H+]=Kw/[OH=(1×1014)/9.49×10=1.05×10–11(molecfpH=ecf[Total:12max3(+)1;(+)2;(+)3;O.N.correspondstotheno.ofelectronsinouter/valencesPCl5fizzesorwhite/mistyfumesorheatPCl5+4H2O→H3PO4+5HClorPCl5+3H2O→HPO3+ rtialhydrolysis:PCl5+H2O→POCl3+(i)P=30.4/31=0.98Cl=69.6/35.5=ThusE.F=Mr(PCl2)=102,so2×PCl2=204≈200,soM.F.=(

(ignorelonepairson ( O.N.= (iv)(HO)2P-P(OH)2orH(HO)P(=O)-P(=O)(OH)H ecffromstructurein()[1]AllowHO-P-OHorHO-P=O[Total: (a)N2+2O2→2NO2(orviaNO)or2NO+O2→ catalyticconver ndpassingtheexhaustgasesoveracatalyst/Pt/Rh ( NO2+2CO→?N2+2CO2or Allow2NO2+CH4→CO2+N2+No,itwouldn’tbereduced.Becausethereactionin(a)doesnotpresupposeaparticularfuel AllowformedfromN2andO2inairduring(d)SO3producesacid(NO+?O2→(Kp=(pNO.pSO)/(pNO2.pSO ptjusta5Kp=99.82/0.22=2.5×Itwillshifttotherightbecausethereaction NOTjustLeier[Total:5reagent+C2H4→HCl,nolightorC2H5OH→concHCl+ZnCl2orSOCl2orPCl5orPCl3andC2H6→Cl2+C2H4→Cl2,nolightorCH3CO2H→SOCl2orPCl5orPCl3andCl2+Cl2+lightor2 (i)productionofNO+:2HSO+HNO→2HSO+HO++NO+ (acceptH2SO4+HNO2

2curlyarrowfromringtoNO+andfromC-Hbondtoring correctintermediate, ludingchargeintherightce2Notechargeareamustbemorethanhalf(Cis(step1:reagentishotacidifiedoralkalinestep2:reagentisBr2+FeBr3/AlCl3etc.(H2Oorlight(IfCisgivenas3-bromotoluene,thenallowthelast[2]marksifsteps1and2are[Total:(a)(i)aqueousalkalineiodineorI2+OH(aq)allowNaClO+KI ( ( Paleyellowppt. eptic ??????

O DforD

(nomark CO2H(allowdisyed,skeletalandstructuralformulae)MustbeconsistentwithF (onlyallowmarkfor allowfor

ifGisthe3-OH(N.B.lettersH,J,Kcanbeswappedaround) [Total:(a)Thetertiary/3-dimensionalstructure/shapeisheldtogetherbyhydrogen/ionic/vanderWaals Thesebreak(relatively)easily/areweak/breakat/above45 (orsimilarEnzyme+ Enzyme-substrate Enzyme+ 3×acompetitiveinhibitorcombineswiththeenzyme’sactivesite(sopreventingthesubstratefrombinding) petitiveinhibitorbondswiththeenzymeawayfromtheactivesite/atlostericthischangestheshapeoftheactive allow inhibitionepetitiveinhibitioncannotberemovedbyreasing[substrate]forthe3rdLinemustbeofsimilarshapetooriginalbutleveloutbeloworiginal ()Inhibitorreducesthenumberofenzymeswith‘working’activesites [Total:(a)partition–separationduetothedifferentsolubilitiesofcompoundsintwoadsorption–separationduetothedifferentattractionsbetweenthecompoundsandthestationaryphase,relativetotheirsolubilityinthesolvent Note,ifcandidatesdonotrefertodifferentsolubilitiesanddifferent maxXX- A+ (i)Xisbromine–Mand(M+2)peaksalmostsameheight (

×

1.1×Hence

p=

(answer+working)(Ifthemasspeakisat122andthecompoundcontainsBrand3CatomsthenQ=(122–79–36))thusQ= ecffrom()(Thecompoundis( (Risatm/e43),hence

AnytwofromH2,H2O,CO,C2H4,C2H2, 2×[Total:(a) ()Anyalkene(orallowacyclicamide, AnyTWO additionneedsunsaturated/doublecondensationneedsamoleculeotherthanaempiricalformulaofadditionpolymeristhesameasthatofitsmonomercondensationneedstwodifferentfunctionalgroups(NOT–“condensationneedstwodifferent 2× ( CH2Correct‘ester’ ‘sticks’torestof Note:candidatesneedonlyshow‘brackets’ifmorethanonerepeatunit( MonomersinTerylenehavetoalternateinordertocondenseoutwater(owtte) Alkenescanlinkinanyorder(andstillformapolyalkene)(ordiagramshowing [Total:GCE20115697019701/414（A2）IGCSE、GCE2011月/62GCEALEVEL20115697011(a)NeqN（非常）N2[1]3Mg(s)→3Mg2+(g).H1=3×148+3×2186=7002N2(g)→2N3–(g).H2=994+22148=LEH1.H246112,753(kJmol–1（i)Li3N3H2ONH33LiOH（平衡方程)是批量過程，而不是連續(xù)過程[1](i)Li3N：10014/3540%N[1]10028/6047%N NH2CONH2+H2O→2NH3+NH2CO2HNH3NH2CONH22H2O2NH3H2CO3污染環(huán)境[1]總數(shù)3GCEALEVEL20115697012(a)(i)owtte)應(yīng)速率[1]Kc=[H+][OH–]/[H2O])KwH+][OH1(i)Kc[H2O][H+][OH&KwKc[H2O(owtte)H2O]Kw[1]i)Kwi)[OH–]=5×10–2;[H+]=(1×10–14)/5×10–2=2×10–13[1]pH=log10[H+]12.7（ans[2]）ecf)[NH4+][OHx)[1x21.810–50.05x[OH9.4910–4(moldm–3)（ansi)[H+]=Kw/[OH–]=(1×10–14)/9.49×10–4=1.05×10–11(molecfiv)pH11.0ecf[1]：123(a)(+)1；(+)2；(+)3;(+)4PCl5[1]PCl54H2OH3PO45HClPCl53H2OHPO35HCl（允許部分水解：PCl5H2OPOCl3i)P30.4/310.98Cl69.6/35.51.96[1]E.FPCl2[1]Mr(PCl2)102，因此2×PCl2=204≈200，因此M.F.=P2Cl4[1])PP（ClCl i)O.N.=(+)2 (HO)2P-P(OH)2H(HO)P(=O)-P(=O)(OH)HHO-P-OHHO-P=OHecf總數(shù)4GCEALEVEL20115/697014(a)N22O22NO2（NO）2NOO22NO2催化轉(zhuǎn)化器并使廢氣通過催化劑/Pt/Rh)NO22CON22CO2[1]2NO2CH4CO2N22H2O(a)owtte)[1]的N2和O2形成d)SO3)Kp=(p.p)/(p.p)SO3NO2Kp=99.82/0.22=2.5×105五它會(huì)向右移動(dòng)(owtte)[1]，因?yàn)榉磻?yīng)是放熱的。不僅僅是勒列的論點(diǎn)轉(zhuǎn)化試劑+條件C2H4→C2H5ClHCl，無光或催化劑C2H5OH→C2H5Cl濃HCl+ZnCl2或SOCl2PCl5PCl3C2H6C2H5ClCl2C2H4C2H4Cl2Cl2，無光或催化劑CH3CO2H→CH3COClSOCl2或PCl5