•
AS
CHEMISTRY
7404/1
Paper 1 Inorganic and Physical Chemistry
v v v v v
Mark scheme v
June 2024
v
Version:v1.0vFinal
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
MarkvschemesvarevpreparedvbyvthevLeadvAssessmentvWritervandvconsidered,vtogethervwithvthevrelevantvqu
estions,vbyvavpanelvofvsubjectvteachers.v Thisvmarkvschemevincludesvanyvamendmentsvmadevatvthevstanda
rdisationveventsvwhichvallvassociatesvparticipatevinvandvisvthevschemevwhichvwasvusedvbyvthemvinvthisvexam
ination.v Thevstandardisationvprocessvensuresvthatvthevmarkvschemevcoversvthevstudents’vresponsesvtovqu
estionsvandvthatveveryvassociatevunderstandsvandvappliesvitvinvthevsamevcorrectvway.
Asvpreparationvforvstandardisationveachvassociatevanalysesvavnumbervofvstudents’vscripts.v Alternativevansw
ersvnotvalreadyvcoveredvbyvthevmarkvschemevarevdiscussedvandvlegislatedvfor.v If,vaftervthevstandardisationvpr
ocess,vassociatesvencountervunusualvanswersvwhichvhavevnotvbeenvraisedvtheyvarevrequiredvtovrefervthesevt
ovthevLeadvExaminer.
Itvmustvbevstressedvthatvavmarkvschemevisvavworkingvdocument,vinvmanyvcasesvfurthervdevelopedvandvexpan
dedvonvthevbasisvofvstudents’vreactionsvtovavparticularvpaper.v Assumptionsvaboutvfuturevmarkvschemesvonvth
evbasisvofvonevyear’svdocumentvshouldvbevavoided;vwhilstvthevguidingvprinciplesvofvassessmentvremainvconst
ant,vdetailsvwillvchange,vdependingvonvthevcontentvofvavparticularvexaminationvpaper.
Novstudentvshouldvbevdisadvantagedvonvthevbasisvofvtheirvgendervidentityvand/orvhowvtheyvrefervtovthevgender
videntityvofvothersvinvtheirvexamvresponses.
Avconsistentvusevofv‘they/them’vasvavsingularvandvpronounsvbeyondv‘she/her’vorv‘he/him’vwillvbevcreditedvinvex
amvresponsesvinvlinevwithvexistingvmarkvschemevcriteria.
Furthervcopiesvofvthisvmarkvschemevarevavailablevfromvaqa.org.uk
Copyrightvinformation
AQAvretainsvthevcopyrightvonvallvitsvpublications.v However,vregisteredvschools/collegesvforvAQAvarevpermittedvtovcopyvmaterialvfromvthisvbookletvforvthe
irvownvinternalvuse,vwithvthevfollowingvimportantvexception:vAQAvcannotvgivevpermissionvtovschools/collegesvtovphotocopyvanyvmaterialvthatvisvacknowled
gedvtovavthirdvpartyvevenvforvinternalvusevwithinvthevcentre.
Copyrightv©v2024vAQAvandvitsvlicensors.v Allvrightsvreserved.
2
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
AS and A-Level Chemistry
v v v
Mark Scheme Instructions for Examiners
v v v v
1. General
Thevmarkvschemevforveachvquestionvshows:
• thevmarksvavailablevforveachvpartvofvthevquestion
• thevtotalvmarksvavailablevforvthevquestion
• thevtypicalvanswervorvanswersvwhichvarevexpected
• extravinformationvtovhelpvthevexaminervmakevhisvorvhervjudgementvandvhelpvtovdelineatevwhatvis
vacceptablevorvnotvworthyvofvcreditvor,vinvdiscursivevanswers,vtovgivevanvoverviewvofvthevareavinv
whichvavmarkvorvmarksvmayvbevawarded.
Thevextravinformationvinvthev‘Comments’vcolumnvisvalignedvtovthevappropriatevanswervinvthevleft-
vhandvpartvofvthevmarkvschemevandvshouldvonlyvbevappliedvtovthatvitemvinvthevmarkvscheme.
Youvshouldvmarkvaccordingvtovthevcontentsvofvthevmarkvscheme.v Ifvyouvarevinvanyvdoubtvaboutvapplyi
ngvthevmarkvschemevtovavparticularvresponse,vconsultvyourvTeamvLeader.
Atvthevbeginningvofvavpartvofvavquestionvavremindervmayvbevgiven,vforvexample:vwherevconsequenti
alvmarkingvneedsvtovbevconsideredvinvavcalculation;vorvthevanswervmayvbevonvthevdiagramvorvatvavdiff
erentvplacevonvthevscript.
Invgeneralvthevright-
handvsidevofvthevmarkvschemevisvtherevtovprovidevthosevextravdetailsvwhichvmightvconfusevthevm
ainvpartvofvthevmarkvschemevyetvmayvbevhelpfulvinvensuringvthatvmarkingvisvstraightforwardvandvc
onsistent.
ThevusevofvM1,vM2,vM3vetcvinvthevright-
handvcolumnvrefersvtovthevmarkingvpointsvinvthevordervinvwhichvtheyvappearvinvthevmarkvscheme.v So,v
M1vrefersvtovthevfirstvmarkingvpoint,vM2vthevsecondvmarkingvpointvetc.
2. Emboldening
2.1 Invavlistvofvacceptablevanswersvwherevmorevthanvonevmarkvisvavailablev‘anyvtwovfrom’visvu
sed,vwithvthevnumbervofvmarksvemboldened.v Eachvofvthevfollowingvbulletvpointsvisvavpote
ntialvmark.
2.2 Avboldvandvisvusedvtovindicatevthatvbothvpartsvofvthevanswervarevrequiredvtovawardvthevm
ark.
2.3 AlternativevanswersvacceptablevforvavmarkvarevindicatedvbyvthevusevofvOR.v Differentvtermsvin
vthevmarkvschemevarevshownvbyvav/v;vegvallowvsmoothv/vfreevmovement.
3. Markingvpoints
3.1 Markingvofvlists
Thisvappliesvtovquestionsvrequiringvavsetvnumbervofvresponses,vbutvforvwhichvstudentsvhave
vprovidedvextravresponses.v Thevgeneralv‘List’vprinciplevtovbevfollowedvinvsuchvavsituationvisvt
hatv‘rightv+vwrongv=vwrong’.
Eachverrorv/vcontradictionvnegatesveachvcorrectvresponse.v So,vifvthevnumbervofverrorv/vcontr
adictionsvequalsvorvexceedsvthevnumbervofvmarksvavailablevforvthevquestion,vnovmarksvcanv
bevawarded.
However,vresponsesvconsideredvtovbevneutralv(oftenvprefacedvbyv‘Ignore’vinvthevmarkvscheme
)varevnotvpenalised.
3
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
Forvexample,vinvavquestionvrequiringv2vanswersvforv2vmarks:
Incorrectvansw
Correctv ersv(ievincorrec
Markv(2) Comment
answers tvrathervthanvne
utral)
1 0 1
Theyvhavevnotvexceededvthevmaximumvnu
1 1 1
mbervofvresponsesvsovtherevisvnovpenalty.
Theyvhavevexceededvthevmaximumvnumberv
1 2 0 ofvresponsesvsovthevextravincorrectvrespons
evcancelsvthevcorrectvone.
2 0 2
2 1 1
2 2 0
3 0 2 Thevmaximumvmarkvisv2
Thevincorrectvresponsevcancelsvoutvonevofvt
3 1 1 hevtwovcorrectvresponsesvthatvgainedvcredit.
Twovincorrectvresponsesvcancelvoutvthevtwovm
3 2 0
arksvgained.
3 3 0
3.2 Markingvprocedurevforvcalculations
Fullvmarksvshouldvbevawardedvforvavcorrectvnumericalvanswer,vwithoutvanyvworkingvshown,
vunlessvthevquestionvstatesv‘Showvyourvworking’vorv‘justifyvyourvanswer’.v Invthisvcase,vthevm
arkvschemevwillvclearlyvindicatevwhatvisvrequiredvtovgainvfullvcredit.
Ifvanvanswervtovavcalculationvisvincorrectvandvworkingvisvshown,vprocessvmark(s)vcanvusually
vbevgainedvbyvcorrectvsubstitutionv/vworkingvandvthisvisvshownvinvthev‘Comments’vcolumnvorv
byveachvstagevofvavlongervcalculation.
3.3 Errorsvcarriedvforward,vconsequentialvmarkingvandvarithmeticverrors
Allowancesvforverrorsvcarriedvforwardvarevmostvlikelyvtovbevrestrictedvtovcalculationvquestion
svandvshouldvbevshownvbyvthevabbreviationvECFvorvconsequentialvinvthevmarkingvscheme.
Anvarithmeticverrorvshouldvbevpenalisedvforvonevmarkvonlyvunlessvotherwisevamplifiedvinvt
hevmarkingvscheme.v Arithmeticverrorsvmayvarisevfromvavslipvinvavcalculationvorvfromvanvin
correctvtransfervofvavnumericalvvaluevfromvdatavgivenvinvavquestion.
3.4 Equations
Invquestionsvrequiringvstudentsvtovwritevequations,vstatevsymbolsvarevgenerallyvignoredvunless
votherwisevstatedvinvthev‘Comments’vcolumn.
Examinersvshouldvalsovcreditvcorrectvequationsvusingvmultiplesvandvfractionsvunlessvotherwis
evstatedvinvthev‘Comments’vcolumn.
4
AS
CHEMISTRY
7404/1
Paper 1 Inorganic and Physical Chemistry
v v v v v
Mark scheme v
June 2024
v
Version:v1.0vFinal
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
MarkvschemesvarevpreparedvbyvthevLeadvAssessmentvWritervandvconsidered,vtogethervwithvthevrelevantvqu
estions,vbyvavpanelvofvsubjectvteachers.v Thisvmarkvschemevincludesvanyvamendmentsvmadevatvthevstanda
rdisationveventsvwhichvallvassociatesvparticipatevinvandvisvthevschemevwhichvwasvusedvbyvthemvinvthisvexam
ination.v Thevstandardisationvprocessvensuresvthatvthevmarkvschemevcoversvthevstudents’vresponsesvtovqu
estionsvandvthatveveryvassociatevunderstandsvandvappliesvitvinvthevsamevcorrectvway.
Asvpreparationvforvstandardisationveachvassociatevanalysesvavnumbervofvstudents’vscripts.v Alternativevansw
ersvnotvalreadyvcoveredvbyvthevmarkvschemevarevdiscussedvandvlegislatedvfor.v If,vaftervthevstandardisationvpr
ocess,vassociatesvencountervunusualvanswersvwhichvhavevnotvbeenvraisedvtheyvarevrequiredvtovrefervthesevt
ovthevLeadvExaminer.
Itvmustvbevstressedvthatvavmarkvschemevisvavworkingvdocument,vinvmanyvcasesvfurthervdevelopedvandvexpan
dedvonvthevbasisvofvstudents’vreactionsvtovavparticularvpaper.v Assumptionsvaboutvfuturevmarkvschemesvonvth
evbasisvofvonevyear’svdocumentvshouldvbevavoided;vwhilstvthevguidingvprinciplesvofvassessmentvremainvconst
ant,vdetailsvwillvchange,vdependingvonvthevcontentvofvavparticularvexaminationvpaper.
Novstudentvshouldvbevdisadvantagedvonvthevbasisvofvtheirvgendervidentityvand/orvhowvtheyvrefervtovthevgender
videntityvofvothersvinvtheirvexamvresponses.
Avconsistentvusevofv‘they/them’vasvavsingularvandvpronounsvbeyondv‘she/her’vorv‘he/him’vwillvbevcreditedvinvex
amvresponsesvinvlinevwithvexistingvmarkvschemevcriteria.
Furthervcopiesvofvthisvmarkvschemevarevavailablevfromvaqa.org.uk
Copyrightvinformation
AQAvretainsvthevcopyrightvonvallvitsvpublications.v However,vregisteredvschools/collegesvforvAQAvarevpermittedvtovcopyvmaterialvfromvthisvbookletvforvthe
irvownvinternalvuse,vwithvthevfollowingvimportantvexception:vAQAvcannotvgivevpermissionvtovschools/collegesvtovphotocopyvanyvmaterialvthatvisvacknowled
gedvtovavthirdvpartyvevenvforvinternalvusevwithinvthevcentre.
Copyrightv©v2024vAQAvandvitsvlicensors.v Allvrightsvreserved.
2
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
AS and A-Level Chemistry
v v v
Mark Scheme Instructions for Examiners
v v v v
1. General
Thevmarkvschemevforveachvquestionvshows:
• thevmarksvavailablevforveachvpartvofvthevquestion
• thevtotalvmarksvavailablevforvthevquestion
• thevtypicalvanswervorvanswersvwhichvarevexpected
• extravinformationvtovhelpvthevexaminervmakevhisvorvhervjudgementvandvhelpvtovdelineatevwhatvis
vacceptablevorvnotvworthyvofvcreditvor,vinvdiscursivevanswers,vtovgivevanvoverviewvofvthevareavinv
whichvavmarkvorvmarksvmayvbevawarded.
Thevextravinformationvinvthev‘Comments’vcolumnvisvalignedvtovthevappropriatevanswervinvthevleft-
vhandvpartvofvthevmarkvschemevandvshouldvonlyvbevappliedvtovthatvitemvinvthevmarkvscheme.
Youvshouldvmarkvaccordingvtovthevcontentsvofvthevmarkvscheme.v Ifvyouvarevinvanyvdoubtvaboutvapplyi
ngvthevmarkvschemevtovavparticularvresponse,vconsultvyourvTeamvLeader.
Atvthevbeginningvofvavpartvofvavquestionvavremindervmayvbevgiven,vforvexample:vwherevconsequenti
alvmarkingvneedsvtovbevconsideredvinvavcalculation;vorvthevanswervmayvbevonvthevdiagramvorvatvavdiff
erentvplacevonvthevscript.
Invgeneralvthevright-
handvsidevofvthevmarkvschemevisvtherevtovprovidevthosevextravdetailsvwhichvmightvconfusevthevm
ainvpartvofvthevmarkvschemevyetvmayvbevhelpfulvinvensuringvthatvmarkingvisvstraightforwardvandvc
onsistent.
ThevusevofvM1,vM2,vM3vetcvinvthevright-
handvcolumnvrefersvtovthevmarkingvpointsvinvthevordervinvwhichvtheyvappearvinvthevmarkvscheme.v So,v
M1vrefersvtovthevfirstvmarkingvpoint,vM2vthevsecondvmarkingvpointvetc.
2. Emboldening
2.1 Invavlistvofvacceptablevanswersvwherevmorevthanvonevmarkvisvavailablev‘anyvtwovfrom’visvu
sed,vwithvthevnumbervofvmarksvemboldened.v Eachvofvthevfollowingvbulletvpointsvisvavpote
ntialvmark.
2.2 Avboldvandvisvusedvtovindicatevthatvbothvpartsvofvthevanswervarevrequiredvtovawardvthevm
ark.
2.3 AlternativevanswersvacceptablevforvavmarkvarevindicatedvbyvthevusevofvOR.v Differentvtermsvin
vthevmarkvschemevarevshownvbyvav/v;vegvallowvsmoothv/vfreevmovement.
3. Markingvpoints
3.1 Markingvofvlists
Thisvappliesvtovquestionsvrequiringvavsetvnumbervofvresponses,vbutvforvwhichvstudentsvhave
vprovidedvextravresponses.v Thevgeneralv‘List’vprinciplevtovbevfollowedvinvsuchvavsituationvisvt
hatv‘rightv+vwrongv=vwrong’.
Eachverrorv/vcontradictionvnegatesveachvcorrectvresponse.v So,vifvthevnumbervofverrorv/vcontr
adictionsvequalsvorvexceedsvthevnumbervofvmarksvavailablevforvthevquestion,vnovmarksvcanv
bevawarded.
However,vresponsesvconsideredvtovbevneutralv(oftenvprefacedvbyv‘Ignore’vinvthevmarkvscheme
)varevnotvpenalised.
3
, MARKvSCHEMEv–vASvCHEMISTRYv–v7404/1v–vJUNEv2024
Forvexample,vinvavquestionvrequiringv2vanswersvforv2vmarks:
Incorrectvansw
Correctv ersv(ievincorrec
Markv(2) Comment
answers tvrathervthanvne
utral)
1 0 1
Theyvhavevnotvexceededvthevmaximumvnu
1 1 1
mbervofvresponsesvsovtherevisvnovpenalty.
Theyvhavevexceededvthevmaximumvnumberv
1 2 0 ofvresponsesvsovthevextravincorrectvrespons
evcancelsvthevcorrectvone.
2 0 2
2 1 1
2 2 0
3 0 2 Thevmaximumvmarkvisv2
Thevincorrectvresponsevcancelsvoutvonevofvt
3 1 1 hevtwovcorrectvresponsesvthatvgainedvcredit.
Twovincorrectvresponsesvcancelvoutvthevtwovm
3 2 0
arksvgained.
3 3 0
3.2 Markingvprocedurevforvcalculations
Fullvmarksvshouldvbevawardedvforvavcorrectvnumericalvanswer,vwithoutvanyvworkingvshown,
vunlessvthevquestionvstatesv‘Showvyourvworking’vorv‘justifyvyourvanswer’.v Invthisvcase,vthevm
arkvschemevwillvclearlyvindicatevwhatvisvrequiredvtovgainvfullvcredit.
Ifvanvanswervtovavcalculationvisvincorrectvandvworkingvisvshown,vprocessvmark(s)vcanvusually
vbevgainedvbyvcorrectvsubstitutionv/vworkingvandvthisvisvshownvinvthev‘Comments’vcolumnvorv
byveachvstagevofvavlongervcalculation.
3.3 Errorsvcarriedvforward,vconsequentialvmarkingvandvarithmeticverrors
Allowancesvforverrorsvcarriedvforwardvarevmostvlikelyvtovbevrestrictedvtovcalculationvquestion
svandvshouldvbevshownvbyvthevabbreviationvECFvorvconsequentialvinvthevmarkingvscheme.
Anvarithmeticverrorvshouldvbevpenalisedvforvonevmarkvonlyvunlessvotherwisevamplifiedvinvt
hevmarkingvscheme.v Arithmeticverrorsvmayvarisevfromvavslipvinvavcalculationvorvfromvanvin
correctvtransfervofvavnumericalvvaluevfromvdatavgivenvinvavquestion.
3.4 Equations
Invquestionsvrequiringvstudentsvtovwritevequations,vstatevsymbolsvarevgenerallyvignoredvunless
votherwisevstatedvinvthev‘Comments’vcolumn.
Examinersvshouldvalsovcreditvcorrectvequationsvusingvmultiplesvandvfractionsvunlessvotherwis
evstatedvinvthev‘Comments’vcolumn.
4
