AAMC MCAT Practice Exam 1 Questions and Answers Updated 2026

AAMC MCAT Practice Exam 1
Questions and Answers
Updated 2026
InBtheBchromatographyBofBtheBreactionBmixture,BwaterBabsorbedBonBcelluloseBfunctio
nedBasBtheBstationaryBphase.BWhatBwasBtheBprincipalBfactorBdeterminingBtheBmigrati
onBofBindividualBcomponentsBinBtheBsample?



A)BHydrogenBbonding

B)BSoluteBconcentration

C)BStationaryBphaseBconcentration

D)BThicknessBofBpaperB-BAnswerBA)BHydrogenBbondingB



TheBAnswerBtoBthisBquestionBisBABbecauseBtheBrelativeBamountBofBhydrogenBbondin
gBtoBtheBstationaryBphaseBwillBdetermineBtheBrelativeBrateBofBmigrationBofBtheBvario
usBcomponentsBinBtheBsample.



WhatBassumptionBisBbeingBmadeBifBscientistsBconcludeBthatBasparticBacidBwasBforme
dBbyBtheBprebiologicalBsynthesisBinBtheBpassage?



A)BAsparticBacidBisBunstableBatBtemperaturesBbelowB150BdegreesBC.B

B)BAllBofBtheBmalicBacidBunderwentBtheBdehydrationBreactionBtoBformBfumaric/maleic
Bacid.B

C)BCompoundBABandBcyanideBwereBavailableBonBprimitiveBEarth.B

D)BTheBreactionBbetweenBammoniaBandBfumaricBacidBwasBcatalyzedBbyBtheBpresence
BofBwater.B-
BAnswerBC)BCompoundBABandBcyanideBwereBavailableBonBprimitiveBEarth.B

,heBAnswerBtoBthisBquestionBisBCBsince,BinBorderBforBtheBexperimentalBreactionBsequ
enceBtoBbeBrelevantBtoBtheBprimordialBformationBofBasparticBacid,BtheBstartingBmater
ialsBusedB(CompoundBABandBcyanide)BareBassumedBtoBhaveBbeenBavailable.



AccordingBtoBtheBdevelopedBchromatographyBplateBshownBbelow,BwhatBisBtheBapproxi
mateBRfBvalueBofBasparticBacid?



asparticBacidB=B2

solventBfrontB=B10B



A)B0.20

B)B0.50

C)B5

D)B10B-
BAnswerBTheBAnswerBtoBthisBquestionBisBAB(0.20)BbecauseBRfBisBtheBratioBofBtheBdi
stanceBtravelledBbyBtheBanalyteBrelativeBtoBtheBsolventBfrontBduringBaBchromatograph
icBseparation.BAsparticBacidBtravelledBtwoBunits,BwhileBtheBsolventBfrontBtravelledBten
Bunits,BgivingBanBRfBofB2/10B=B0.20BforBasparticBacid.



WhichBofBtheBfollowingBstatementsBdoesBNOTBcorrectlyBdescribeBtheBdehydrationBofB
malicBacidBtoBfumaricBacidBandBmaleicBacid?B



A)BTheBreactionBoccursBmostBreadilyBwithBtertiaryBalcohols.B

B)BTheBreactionBinvolvesBtheBlossBofBaBwaterBmolecule.B

C)BTheBreactionBhasBaBcarbocationBintermediate.

D)BTheBreactionBisBstereospecific.B-BAnswerBD)BTheBreactionBisBstereospecific.



TheBAnswerBtoBthisBquestionBisBDBbecauseBtheBfactBthatBbothBfumaricBandBmaleicBa
cidBareBproducedBmeansBthatBtheBdehydrationBofBmalicBacidBisBNOTBstereospecific.

,WhatBtypeBofBfunctionalBgroupBisBformedBwhenBasparticBacidBreactsBwithBanotherBa
minoBacidBtoBformBaBpeptideBbond?B



A)BAnBamineBgroupB

B)BAnBaldehydeBgroup

C)BAnBamideBgroup

D)BABcarboxylBgroupB-BAnswerBC)BAnBamideBgroup



TheBAnswerBtoBthisBquestionBisBCBbecauseBtheBfunctionalBgroupBthatBformsBduringBp
eptideBbondBformationBisBknownBasBanBamideBgroup.



IfB2-pentanolBreplacesB1-
pentanolBinBtheBreactionBshownBinBFigureB3B(SN2),BtheBrateBofBsubstitutionBisBlessBb
ecause:B

A)BtheBC-OBbondBinB2-pentanolBisBstrongerBthanBtheBC-OBbondBinB1-pentanol.

B)BthereBisBaBcompetingBeliminationBreactionBthatBslowsBtheBrateBofBsubstitution.

C)BthereBisBmoreBstericBhindranceBatBtheBoxygenBatomBinB2-pentanolBthanBinB1-
pentanol,BmakingBprotonationBlessBlikely.

D)BthereBisBmoreBstericBhindranceBatBtheB2-positionBofB2-pentanolBthanBatBtheB1-
positionBofB1-pentanol.B-BAnswerBD)BthereBisBmoreBstericBhindranceBatBtheB2-
positionBofB2-pentanolBthanBatBtheB1-positionBofB1-pentanol.



TheBAnswerBtoBthisBquestionBisBDBbecauseBtheBrateBofBsubstitutionBofBprotonatedBal
coholsBisBsubjectBtoBstericBhindrance.BThisBinhibitsBtheBabilityBofBnucleophilesBtoBcolli
deBwithBtheBreactingBelectrophilicBcenterBandBslowsBtheBrateBofBreaction.



IfBaBsolutionBcontainingBtheBcompoundsBshownBinBFigureB4,BisBinjectedBintoBaBgas-
liquidBchromatograph,BtheBfirstBpeakBobservedBinBtheBgcBtraceBisBattributableBtoBwhi
chBcompound?

A)BMethyl-2-butanol

B)BMethyl-2-butene

, C)BChloro-2-methylbutane

D)BBromo-2-mehtylbutaneB-BAnswerBB)BMethyl-2-butene



TheBAnswerBtoBthisBquestionBisBBBbecauseB2-methyl-2-
buteneBwillBexhibitBtheBlowestBmolecularBweightBandBalsoBtheBweakestBintermolecula
rBforcesBofBattraction.BThisBsubstanceBwillBthereforeBmigrateBtheBfastestBandBbeBtheB
firstBpeakBinBtheBgasBchromatographB(gc)Btrace.



RBvs.BSBstereochemistry*B-BAnswerBRB=Bclockwise

CB=Bcounter-clockwise



AceticBacidBandBethanolBreactBtoBformBanBesterBproductBasBshownBbelow.B



InBdeterminingBwhichBreactantBlosesBtheB-
OHBgroup,BwhichBofBtheBfollowingBisotopicBsubstitutionsBwouldBbeBmostBuseful?



A)BReplaceBtheBacidicBHBofBaceticBacidBwithBD

B)BReplaceBtheBalcoholicBHBofBethanolBwithBD.B

C)BReplaceBtheBcarbonylBoxygenBofBaceticBacidBwithBO-18.B

D)BReplaceBtheBhydroxylBoxygenBofBethanolBwithBO-18.B-
BAnswerBD)BReplaceBtheBhydroxylBoxygenBofBethanolBwithBO-18.



TheBAnswerBtoBthisBquestionBisBDBbecauseBthisBexperimentBinvolvesBlabelingBaBgroup
BwhichBdoesBnotBexchangeBwithBotherBgroupsBpresentBpriorBtoBreactionBandBwillBthe
reforeBgiveBinformationBaboutBtheBtrueBidentityBofBtheBgroups,BwhichBareBexchanged
BduringBtheBreaction.



ABpersonBwhoseBeyeBhasBaBlens-to-
retinaBdistanceBofB2.0Bcm,BcanBonlyBclearlyBseeBobjectsBthatBareBcloserBthanB1.0BmB
away.BWhatBisBtheBstrengthBSBofBtheBperson'sBeyeBlens?B(Note:BUseBtheBthinBlensBf
ormulaB1/OB+B1/IB=BS)B