Test Bank For Essential Biochemistry, 17th Edition All Chapters - 9781119712855.pdf

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1. ThefdipolefmomentfinfafwaterfmoleculefWhichfstatementfaboutfhydrogenfbondsfisfNOTftru
e?
A) Hydrogenfbondsfaccountfforfthefanomalouslyfhighfboilingfpointfoffwater.
B) Infliquidfwater,fthefaveragefwaterfmoleculefformsfhydrogenfbondsfwithfthreeftoffou
rfotherfwaterfmolecules.
C) Individualfhydrogenfbondsfarefmuchfweakerfthanfcovalentfbonds.
D) Individualfhydrogenfbondsfinfliquidfwaterfexistfforfmanyfsecondsfandfsometimesffor
fminutes.

E) Thefstrengthfoffafhydrogenfbondfdependsfonftheflinearityfoffthefthreefatomsfinv
olvedfinfthefbond.


2. AfTRUEfstatementfaboutfhydrophobicfinteractionsfisfthatfthey:
A) arefthefdrivingfforcefinfthefformationfoffmicellesfoffamphipathicfcompoundsfinfwa
ter.
B) dofnotfcontributeftofthefstructurefoffwater-solublefproteins.
C) havefbondingfenergiesfoffapproximatelyf20–40fKjoulefperfmole.
D) involvefthefabilityfoffwaterftofdenaturefproteins.
E) primarilyfinvolvefthefeffectfoffpolarfsolutesfonfthefentropyfoffaqueousfsystems.



3. Hydrophobicfinteractionsfmakefimportantfenergeticfcontributionsfto:
A) bindingfoffafhormoneftofitsfreceptorfprotein.
B) enzyme-substratef interactions.
C) membranefstructure.
D) three-dimensionalffoldingfoffafpolypeptidefchain.
E) Allfoffthefanswersfarefcorrect.



4. Dissolvedfsolutesfalterfsomefphysicalf(colligative)fpropertiesfoffthefsolventfwaterfbe
causeftheyfchangefthe:
A) concentrationfoffthefwater.
B) hydrogenfbondingfoffthefwater.
C) ionicfbondingfoffthefwater.
D) pHfoffthefwater.



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E) temperaturefoffthefwater.



5. Osmosisfisfmovementfoffa:
A) chargedfsolutefmoleculef(ion)facrossfafmembrane.
B) gasfmoleculefacrossfafmembrane.
C) nonpolarfsolutefmoleculefacrossfafmembrane.
D) polarfsolutefmoleculefacrossfafmembrane.
E) waterfmoleculefacrossfafmembrane.



6. Afhydroniumfion:
A) hasfthefstructurefH3O+.
B) isfafhydratedfhydrogenfion.
C) isfafhydratedfproton.
D) isfthefusualfformfoffonefoffthefdissociationfproductsfoffwaterfinfsolution.
E) Allfoffthefanswersfarefcorrect.



7. ThefpHfoffafsolutionfoff1fMfHClfis:
A) 0.
B) 0.1.
C) 1.
D) 10.
E) –1.



8. ThefpHfoffafsolutionfoff0.1fMfNaOHfis:
A) 0.1.
B) 1.0.
C) 12.8.
D) 13.
E) 14.




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9. WhichfstatementfisfTRUEfaboutfthefpropertiesfoffaqueousfsolutions?
A) AfpHfchangeffromf5.0ftof6.0freflectsfanfincreasefinfthefhydroxidefionfconcentrationf([O
H–])foff20%.
B) AfpHfchangeffromf8.0ftof6.0freflectsfafdecreasefinfthefprotonfconcentrationf([H+])fbyfa
ffactorfoff100.

C) Chargedfmoleculesfarefgenerallyfinsolublefinfwater.
D) Hydrogenfbondsfformfreadilyfinfaqueousfsolutions.
E) ThefpHfcanfbefcalculatedfbyfaddingf7ftofthefvaluefoffthefpOH.



10. ThefpHfoffafsamplefoffbloodfisf7.4,fwhilefgastricfjuicefisfpHf1.4.f Thefbloodfsamplefhas:
A) 0.189ftimesfthef[H+]fasfthefgastricfjuice.
B) 5.29ftimesflowerf[H+]fthanfthefgastricfjuice.
C) 6ftimesflowerf[H+]fthanfthefgastricfjuice.
D) 6000ftimesflowerf[H+]fthanfthefgastricfjuice.
E) onefmillionftimesflowerf[H+]fthanfthefgastricfjuice.



11. ThefaqueousfsolutionfwithfthefLOWESTfpHfis:
A) 0.01fMfHCl.
B) 0.1fMfaceticfacidf(pKaf=f4.86).
C) 0.1fMfformicfacidf(pKaf=f3.75).
D) 0.1fMfHCl.
E) 10–12fMfNaOH.



12. ThefaqueousfsolutionfwithfthefHIGHESTfpHfis:
A) 1fMfHCl.
B) 1fMfNH3f(pKaf=f9.25).
C) 0.5fMfNaHCO3f(pKaf=f3.77).
D) 0.1fMfNaOH.
E) 0.001fMfNaOH.




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13. Phosphoricfacidfisftribasic,fwithfpKa'sfoff2.14,f6.86,fandf12.4.fThefionicfformfthatfpre
dominatesfatfpHf3.2fis:
A) H3PO4.
B) H2PO–4.
C) HPOf42–.
D) POf43–.
E) Nonefoffthefanswersfisfcorrect.



14. WhichfstatementfaboutfbuffersfisfTRUE?
A) AfbufferfcomposedfoffafweakfacidfoffpKaf=f5fisfstrongerfatfpHf4fthanfatfpHf6.
B) AtfpHfvaluesflowerfthanfthefpKa,fthefsaltfconcentrationfisfhigherfthanfthatfoffthefacid
.
C) ThefpHfoffafbufferedfsolutionfremainsfconstantfnofmatterfhowfmuchfacidforfbasefisfadd
edftofthefsolution.
D) Thefstrongestfbuffersfarefthosefcomposedfoffstrongfacidsfandfstrongfbases.
E) WhenfpHf=fpKa,fthefweakfacidfandfsaltfconcentrationsfinfafbufferfarefequal.



15. AfcompoundfhasfafpKafoff7.4.f Tof100fmLfoffaf1.0fMfsolutionfoffthisfcompoundfatfpH
8.0fisfaddedf30fmLfoff1.0fMfhydrochloricfacid.fThefresultingfsolutionfisfpH:
A) 6.5.
B) 6.8.
C) 7.2.
D) 7.4.
E) 7.5.



16. ThefHenderson-Hasselbalchfequation:
A) allowsfthefgraphicfdeterminationfoffthefmolecularfweightfoffafweakfacidffromfitsfpHf
alone.
B) doesfnotfexplainfthefbehaviorfoffdi-forftri-basicfweakfacids.
C) employsfthefsamefvaluefforfpKafforfallfweakfacids.
D) isfequallyfusefulfwithfsolutionsfoffaceticfacidfandfoffhydrochloricfacid.
E) relatesfthefpHfoffafsolutionftofthefpKafandfthefconcentrationsfoffacidfandfconjugatefbas
e.




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