BioChemistry Test Bank (All 23 chapters complete, Questions and Answers with complete solutions

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1. ThegdipolegmomentgingagwatergmoleculegWhichgstatementgaboutghydrogengbondsgisgNO
Tgtrue?
A) Hydrogengbondsgaccountgforgtheganomalouslyghighgboilinggpointgofgwater.
B) Ingliquidgwater,gthegaveragegwatergmoleculegformsghydrogengbondsgwithgthreeg
togfourgothergwatergmolecules.
C) Individualghydrogengbondsgaregmuchgweakergthangcovalentgbonds.
D) Individualghydrogengbondsgingliquidgwatergexistgforgmanygsecondsgandgsometim
esgforgminutes.
E) Thegstrengthgofgaghydrogengbondgdependsgongtheglinearitygofgthegthreegato
msginvolvedgingthegbond.


2. AgTRUEgstatementgaboutghydrophobicginteractionsgisgthatgthey:
A) aregthegdrivinggforcegingthegformationgofgmicellesgofgamphipathicgcompoundsg
ingwater.
B) dognotgcontributegtogthegstructuregofgwater-solublegproteins.
C) havegbondinggenergiesgofgapproximatelyg20–40gKjoulegpergmole.
D) involvegthegabilitygofgwatergtogdenaturegproteins.
E) primarilyginvolvegthegeffectgofgpolargsolutesgongthegentropygofgaqueousgsystems.



3. Hydrophobicginteractionsgmakegimportantgenergeticgcontributionsgto:
A) bindinggofgaghormonegtogitsgreceptorgprotein.
B) enzyme-substrateg interactions.
C) membranegstructure.
D) three-dimensionalgfoldinggofgagpolypeptidegchain.
E) Allgofgtheganswersgaregcorrect.



4. Dissolvedgsolutesgaltergsomegphysicalg(colligative)gpropertiesgofgthegsolventgwat
ergbecausegtheygchangegthe:
A) concentrationgofgthegwater.
B) hydrogengbondinggofgthegwater.
C) ionicgbondinggofgthegwater.
D) pHgofgthegwater.



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E) temperaturegofgthegwater.



5. Osmosisgisgmovementgofga:
A) chargedgsolutegmoleculeg(ion)gacrossgagmembrane.
B) gasgmoleculegacrossgagmembrane.
C) nonpolargsolutegmoleculegacrossgagmembrane.
D) polargsolutegmoleculegacrossgagmembrane.
E) watergmoleculegacrossgagmembrane.



6. Aghydroniumgion:
A) hasgthegstructuregH3O+.
B) isgaghydratedghydrogengion.
C) isgaghydratedgproton.
D) isgthegusualgformgofgonegofgthegdissociationgproductsgofgwatergingsolution.
E) Allgofgtheganswersgaregcorrect.



7. ThegpHgofgagsolutiongofg1gMgHClgis:
A) 0.
B) 0.1.
C) 1.
D) 10.
E) –1.



8. ThegpHgofgagsolutiongofg0.1gMgNaOHgis:
A) 0.1.
B) 1.0.
C) 12.8.
D) 13.
E) 14.




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9. WhichgstatementgisgTRUEgaboutgthegpropertiesgofgaqueousgsolutions?
A) AgpHgchangegfromg5.0gtog6.0greflectsgangincreasegingtheghydroxidegiongconcentrati
ong([OH–])gofg20%.
B) AgpHgchangegfromg8.0gtog6.0greflectsgagdecreasegingthegprotongconcentrationg([H
+
])gbygagfactorgofg100.
C) Chargedgmoleculesgareggenerallyginsolublegingwater.
D) Hydrogengbondsgformgreadilygingaqueousgsolutions.
E) ThegpHgcangbegcalculatedgbygaddingg7gtogthegvaluegofgthegpOH.



10. ThegpHgofgagsamplegofgbloodgisg7.4,gwhileggastricgjuicegisgpHg1.4.g Thegbloodgsampleghas:
A) 0.189gtimesgtheg[H+]gasgtheggastricgjuice.
B) 5.29gtimesglowerg[H+]gthangtheggastricgjuice.
C) 6gtimesglowerg[H+]gthangtheggastricgjuice.
D) 6000gtimesglowerg[H+]gthangtheggastricgjuice.
E) onegmilliongtimesglowerg[H+]gthangtheggastricgjuice.



11. ThegaqueousgsolutiongwithgthegLOWESTgpHgis:
A) 0.01gMgHCl.
B) 0.1gMgaceticgacidg(pKag=g4.86).
C) 0.1gMgformicgacidg(pKag=g3.75).
D) 0.1gMgHCl.
E) 10–12gMgNaOH.



12. ThegaqueousgsolutiongwithgthegHIGHESTgpHgis:
A) 1gMgHCl.
B) 1gMgNH3g(pKag=g9.25).
C) 0.5gMgNaHCO3g(pKag=g3.77).
D) 0.1gMgNaOH.
E) 0.001gMgNaOH.




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13. Phosphoricgacidgisgtribasic,gwithgpKa'sgofg2.14,g6.86,gandg12.4.gThegionicgformgth
atgpredominatesgatgpHg3.2gis:
A) H3PO4.
B) H2PO–4.
C) HPOg42–.
D) POg43–.
E) Nonegofgtheganswersgisgcorrect.



14. WhichgstatementgaboutgbuffersgisgTRUE?
A) AgbuffergcomposedgofgagweakgacidgofgpKag=g5gisgstrongergatgpHg4gthangatgpHg6.
B) AtgpHgvaluesglowergthangthegpKa,gthegsaltgconcentrationgisghighergthangthatgofgt
hegacid.
C) ThegpHgofgagbufferedgsolutiongremainsgconstantgnogmatterghowgmuchgacidgorgbase
gisgaddedgtogthegsolution.

D) Thegstrongestgbuffersgaregthosegcomposedgofgstronggacidsgandgstronggbases.
E) WhengpHg=gpKa,gthegweakgacidgandgsaltgconcentrationsgingagbuffergaregequal.



15. AgcompoundghasgagpKagofg7.4.g Tog100gmLgofgag1.0gMgsolutiongofgthisgcompoundgatgpH
8.0gisgaddedg30gmLgofg1.0gMghydrochloricgacid.gThegresultinggsolutiongisgpH:
A) 6.5.
B) 6.8.
C) 7.2.
D) 7.4.
E) 7.5.



16. ThegHenderson-Hasselbalchgequation:
A) allowsgtheggraphicgdeterminationgofgthegmoleculargweightgofgagweakgacidgfromgi
tsgpHgalone.
B) doesgnotgexplaingthegbehaviorgofgdi-gorgtri-basicgweakgacids.
C) employsgthegsamegvaluegforgpKagforgallgweakgacids.
D) isgequallygusefulgwithgsolutionsgofgaceticgacidgandgofghydrochloricgacid.
E) relatesgthegpHgofgagsolutiongtogthegpKagandgthegconcentrationsgofgacidgandgconjuga
tegbase.




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