2017 Chemistry Written examination - vcaa.vic.edu.au · PDF filemoves the chemical equilibrium of a reaction in the forward ... , which one of the following fatty acids is likely to

CHEMISTRYWritten examination

Tuesday 14 November 2017 Reading time: 9.00 am to 9.15 am (15 minutes) Writing time: 9.15 am to 11.45 am (2 hours 30 minutes)

QUESTION AND ANSWER BOOK

Structure of bookSection Number of

questionsNumber of questions

to be answeredNumber of

marksA 30 30 30B 10 10 90

Total 120

• Studentsarepermittedtobringintotheexaminationroom:pens,pencils,highlighters,erasers, sharpeners,rulersandonescientificcalculator.

• StudentsareNOTpermittedtobringintotheexaminationroom:blanksheetsofpaperand/orcorrectionfluid/tape.

Materials supplied• Questionandanswerbookof37pages• Databook• Answersheetformultiple-choicequestionsInstructions• Writeyourstudent numberinthespaceprovidedaboveonthispage.• Checkthatyourname andstudent numberasprintedonyouranswersheetformultiple-choice

questionsarecorrect,andsignyournameinthespaceprovidedtoverifythis.• Unlessotherwiseindicated,thediagramsinthisbookarenotdrawntoscale.• AllwrittenresponsesmustbeinEnglish.At the end of the examination• Placetheanswersheetformultiple-choicequestionsinsidethefrontcoverofthisbook.• Youmaykeepthedatabook.

Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room.

©VICTORIANCURRICULUMANDASSESSMENTAUTHORITY2017

SUPERVISOR TO ATTACH PROCESSING LABEL HEREVictorian Certificate of Education 2017

STUDENT NUMBER

Letter

2017CHEMISTRYEXAM 2

SECTION A – continued

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eaQuestion 1

AcatalystA. slowstherateofreaction.B. ensuresthatareactionisexothermic.C. movesthechemicalequilibriumofareactionintheforwarddirection.D. providesanalternativepathwayforthereactionwithaloweractivationenergy.

Question 2Lithium-ionrechargeablebatteriesareusedinmobilephones.Environmentalconditionscanaffectthenumberofchargecyclesforalithium-ionbatteryuntiltheendofitsusefullife.Whichofthefollowingenvironmentalconditionswouldbeexpectedtoresultinthelargestnumberofchargecyclesforalithium-ionbattery?

Minimum temperature (°C)

Maximum temperature (°C)

A. –8 11

B. 9 21

C. 18 37

D. 28 40

Question 3AhydrolyticreactionoccurswhenA. adipeptideisformed.B. atriglycerideisformed.C. waterisareactionproduct.D. glucoseisformedfrommaltose.

SECTION A – Multiple-choice questions

Instructions for Section AAnswerall questionsinpencilontheanswersheetprovidedformultiple-choicequestions.Choosetheresponsethatiscorrect orthatbest answers thequestion.Acorrectanswerscores1;anincorrectanswerscores0.Markswillnotbedeductedforincorrectanswers.Nomarkswillbegivenifmorethanoneansweriscompletedforanyquestion.Unlessotherwiseindicated,thediagramsinthisbookarenotdrawntoscale.

3 2017 CHEMISTRY EXAM

SECTION A – continuedTURN OVER

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Question 4Which of the following contains a chiral carbon?

Name Semi-structural formula

A. 2-methylbut-1-ene CH2C(CH3)CH2CH3

B. 2-chlorobutane CH3CHClCH2CH3

C. propanoic acid CH3CH2COOH

D. 1,2-dichloroethene ClCHCHCl

Question 5Which one of the following is a biofuel?A. ethanol produced from crude oilB. ethanol produced from celluloseC. propane produced from natural gasD. electricity produced by hydropower

Question 6The overall equation for a particular methanol fuel cell is shown below.

2CH3OH(g) + 3O2(g) → 2CO2(g) + 4H2O(l)

The equation for the reaction that occurs at the cathode in this fuel cell isA. CO2(g) + 5H2O(l) + 6e– → CH3OH(g) + 6OH–(aq)B. CH3OH(g) + 6OH–(aq) → CO2(g) + 5H2O(l) + 6e–

C. O2(g) + 2H2O(l) + 4e– → 4OH–(aq)D. 4OH–(aq) → O2(g) + 2H2O(l) + 4e–

Question 7What is the total energy released, in kilojoules, when 100 g of butane and 200 g of octane undergo combustion in the presence of excess oxygen?A. 9760B. 14 600C. 17 300D. 19 500

Question 8An enzymeA. can distinguish between optical isomers.B. catalyses forward and reverse reactions.C. always needs a coenzyme to function.D. is not able to change shape.

2017CHEMISTRYEXAM 4


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Question 9Thenutritioninformationpanelonapacketofmuesliincludesthefollowinginformation.

Nutrition informationaverageservingsize=45g

Average quantity per 100 g

protein 13.2g

fat,total 16.3g

–saturated 2.9g

carbohydrate,total 48.2g

–sugars 17.4g

dietaryfibre 4.9g

sodium 10.5mg

Usingtheinformationabove,thepercentageenergycontentduetoproteininanaverageservingsizeofthismuesliisA. 31.2%B. 29.3%C. 14.0%D. 13.2%

Question 10Whichoneofthefollowingstructuresrepresentsazwitterionofa2-aminoacid?

H2N CH COO–

CH2 C

O

NH2

H3N+ CH COO–

COO–CH2 CH2

H3N+ CH COOH

CH3 CH3CH

H3N+ CH COO–

CH2 OH

A. B.

C. D.

5 2017CHEMISTRYEXAM


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Question 11Agalvaniccellconsistsoftwoconnectedhalf-cellsthatcanproduceanelectronflow.Whichcombinationofstandardhalf-cellpairswouldbeexpectedtoresultinacellpotentialof1.41V?

A. AlelectrodewithAl(NO3)3 AgelectrodewithAgNO3

B. ZnelectrodewithZn(NO3)2 NielectrodewithNi(NO3)2

C. NielectrodewithNi(NO3)2 AlelectrodewithAl(NO3)3

D. AgelectrodewithAgNO3 ZnelectrodewithZn(NO3)2

Question 12Whenstoredunderidenticalconditions,whichoneofthefollowingfattyacidsislikelytoundergooxidativerancidityintheshortesttime?A. linolenicacidB. linoleicacidC. stearicacidD. oleicacid

2017 CHEMISTRY EXAM 6


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Use the following information to answer Questions 13 and 14.Four identical vehicle models, 1, 2, 3 and 4, were tested for fuel efficiency using LPG, petrol (unleaded, 91 octane), E10 (petrol with 10% ethanol added) and petrodiesel. Carbon dioxide, CO2, emissions per litre of fuel burnt were also determined. The following table summarises the results.

Vehicle model

Fuel Fuel consumption (L/100 km)

CO2 produced (g CO2/L of fuel)

1 LPG 19.7 1665

2 petrol 14.5 2392

3 E10 14.2 2304

4 petrodiesel 9.2 2640

Question 13Using the information in the table above, which one of the following statements about petrodiesel is correct?A. It has the highest energy content.B. It has the poorest fuel efficiency.C. It is a renewable energy source.D. It has the lowest CO2 emissions when burnt.

Question 14The use of which vehicle has the smallest impact on the environment, in terms of the grams of CO2 produced per 100 km?A. Vehicle model 1B. Vehicle model 2C. Vehicle model 3D. Vehicle model 4

Question 15Which one of the following is a correct statement about the denaturation of a protein?A. Denaturation is characterised by the release of peptides. B. Alcohol denatures proteins by disrupting the hydrogen bonding.C. Denaturation involves disruption of all bonds in the tertiary structure.D. The primary and secondary structures are disrupted when denaturation occurs.



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Question 16A patient’s blood tests indicate clinically low levels of vitamins C and D.Which one of the following recommendations would most effectively and safely increase the patient’s levels of both vitamins C and D?A. Take a supplement of oil containing vitamin D regularly and eat citrus fruit daily.B. Eat more dairy products and spend one hour per day in the sun wearing sun protection.C. Dissolve a vitamin C tablet and a vitamin D tablet in a glass of water each morning and drink it.D. Eat more green leafy vegetables and spend one hour per day in the sun without wearing sun protection.

Question 17Shown below is the infra-red spectrum of an organic compound.

100

50

0

transmittance

4000 3000 2000wave number (cm–1)

1500 1000 500

Data: SDBS Web, <http://sdbs.db.aist.go.jp>, National Institute of Advanced Industrial Science and Technology

The organic compound that produces this spectrum is an A. aldehyde.B. alcohol.C. amide.D. ester.

Question 18 Ammonia, NH3, can be produced by the reaction of hydrogen, H2, and nitrogen, N2. When this reaction takes place in a sealed container of fixed volume, an equilibrium system is established. The equation for the reaction is shown below.

N2(g) + 3H2(g) ⇌ 2NH3(g) ΔH = –92 kJ mol–1

If the pressure and volume remain constant when the temperature is increased, the forward reaction rate willA. increase and the [NH3] will increase.B. increase and the [NH3] will decrease.C. decrease and the [NH3] will decrease.D. decrease and the [NH3] will remain the same.

2017CHEMISTRYEXAM 8


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Question 19AYear12Chemistryassignmentrequiresstudentstoquantitativelyandqualitativelycomparefossilfuelsandbiofuels.Whichoneofthefollowinginvestigationswouldbemostappropriateforthiscomparison?A. Useabombcalorimetertodeterminetheheatofcombustionforbothfossilfuelsandbiofuels.B. Interviewcarownerstodeterminewhatpetrolpricewouldmakethemconsiderusingbiofuels.C. Producebiodieselfromvegetableoilandcomparetheviscosityofthebiodieselproducedwiththatofarangeof

fossilfuels.D. Findreliableinformationabouttheenvironmentalimpactsofproducingfossilfuelsandbiofuels,andthe

amountofcarbondioxideproducedperlitrefromthecombustionofthesefuels.

Question 20Thereactionbelowrepresentsthedischargecycleofastandardlead-acidrechargeablecarbattery.

Pb(s)+PbO2(s)+4H+(aq)+2SO42–(aq)→2PbSO4(s)+2H2O(l)

Duringtherechargecycle,thepHA. increasesandsolidPbisareactant.B. increasesandsolidPbO2isproduced.C. decreasesandchemicalenergyisconvertedtoelectricalenergy.D. decreasesandelectricalenergyisconvertedtochemicalenergy.

9 2017CHEMISTRYEXAM


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Use the following information to answer Questions 21 and 22.Themassofcaffeineinaparticularcoffeedrinkwasdeterminedbyhigh-performanceliquidchromatography(HPLC).ThecalibrationcurveproducedfromrunningstandardsolutionsofcaffeinethroughanHPLCcolumnisshownbelow.

5000

4000

3000peak area

(arbitrary units)

2000

1000

00.0100 0.020 0.030

concentration (g/L)0.040 0.050 0.060

A5.0mLaliquotofthecoffeedrinkwasdilutedto50.0mLwithde-ionisedwater.AsampleofthedilutedcoffeedrinkwasrunthroughtheHPLCcolumnunderidenticalconditionstothoseusedtoobtainthecalibrationcurve.Thepeakareaobtainedforthisdilutedsamplewas2400arbitraryunits.

Question 21TheHPLCcolumnusedhasanon-polarstationaryphase.ThemostsuitablesolventfordeterminingtheconcentrationofcaffeineinthesampleisA. carbontetrachloride,CCl4B. methanol,CH3OHC. octanol,C8H17OHD. hexane,C6H14

Question 22Themassofcaffeine,ingrams,in350mLoftheundilutedcoffeedrinkisclosesttoA. 0.014B. 0.070C. 0.14D. 0.40

2017CHEMISTRYEXAM 10


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Question 23Theheatofcombustionofasampleofcrudeoilistobedeterminedusingabombcalorimeter.Allofthestudentsinaclassaregiventhesamemethodtofollow.Theapparatususedbythestudentsisshownbelow.

thermometer

insulatedcontainer

sealed vessel sample of crude oil

stirrer

ignition wire

water

oxygen (excess)

Forthisexperiment,thestudentscouldmaximiseA. precisionbyusingadigitalthermometer±0.2°C.B. validitybycalculatingtheheatofcombustionpermole.C. accuracybytakingsamplesfromthreedifferentsources.D. uncertaintybyhavingallstudentscloselyfollowthesameexperimentalprocedure.

11 2017CHEMISTRYEXAM


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Question 24Asampleofoliveoilwithawickinajarisignitedandusedtoheatabeakercontaining500.0gofwater,H2O.Therelevantdatafortheexperimentisincludedinthetablebelow.

500.0 g H2O

wick

olive oil

beakerData

initialtemperature(H2O) 21.0°C

ΔH(oliveoil) 41.0kJg–1

totalenergylosttotheenvironment

28.0kJ

Aftercompletecombustionof2.97gofoliveoil,thefinaltemperatureofthewater,indegreesCelsius,wouldbeA. 44.9B. 58.0C. 65.9D. 79.3

Question 25Theglycaemicindex(GI)indicateshowquicklycarbohydratesinfoodarebrokendownandraiseaperson’sbloodglucoselevel.Thetablebelowshowsthepercentageofamyloseandamylopectininthecarbohydratecontentoffourfoods,P,Q,RandS.Basedonthisinformation,whichoneofthefoodslistedwouldbeexpectedtohavethelowestGIvalue?

Food Amylose (%) Amylopectin (%)

A. P 30 70

B. Q 24 76

C. R 14 86

D. S 20 80

Question 2610gofcarbondioxide,CO2,gasisinjectedintoasealed,evacuated12Lvesselat30°C.Afterafurther1gofCO2gasisinjectedintothevessel,whatisthetemperaturechange,indegreesCelsius,requiredtomaintaintheoriginalpressure?A. –28B. –3.7C. +3.7D. +28



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Use the following information to answer Questions 27 and 28.Anincreasinglypopularbatteryforstoringenergyfromsolarpanelsisthevanadiumredoxbattery.Thebatterytakesadvantageofthefouroxidationstatesofvanadiumthatarestableinaqueousacidicsolutionsintheabsenceofoxygen.Aschematicdiagramofavanadiumredoxbatteryisshownbelow.

electrode

electrode

solar panels devices/gridswitch

V2+(aq) / V3+(aq)in

H2SO4(aq)

VO2+(aq) / VO2+(aq)

inH2SO4(aq)

membranefor H+

exchangeElectrolyte 1 Electrolyte 2

wires

Thetworelevanthalf-equationsforthebatteryareasfollows.

VO2+(aq)+2H+(aq)+e– →VO2+(aq)+H2O(l) E0=+1.00V

V3+(aq)+e– → V2+(aq) E0=–0.26V

Question 27TheoverallreactionthatoccurswhenthebatteryisdischargingisA. VO2

+(aq)+2H+(aq)+V2+(aq)→VO2+(aq)+V3+(aq)+H2O(l)B. VO2+(aq)+H2O(l)+V3+(aq)→VO2

+(aq)+V2+(aq)+2H+(aq)C. VO2+(aq)+V2+(aq)+2H+(aq)→ 2V3+(aq)+H2O(l)D. VO2

+(aq)+V3+(aq)→2VO2+(aq)



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Question 28If air is present, the following half-equations are also relevant.

O2(g) + 4H+(aq) + 4e– → 2H2O(l) E0 = +1.23 VVO2+(aq) + 2H+(aq) + e– → V3+(aq) + H2O(l) E0 = +0.34 V

If air is present, theA. VO2+(aq) ion is oxidised to the V2+(aq) ion.B. VO2+(aq) ion is reduced to the V3+(aq) ion.C. V2+(aq) ion is oxidised to the VO2+(aq) ion.D. VO2

+(aq) ion is reduced to the VO2+(aq) ion.

Question 29The following energy profile shows the results obtained during an enzyme-catalysed reaction. Each stage of the reaction is labelled: M represents the initial reactants, N represents a stable intermediate and P represents the final products.

energy

M

N

P

Which one of the following statements is correct?A. The energy change from M to N is exothermic and the energy change from N to P is exothermic.B. The energy change from M to P is exothermic and the energy change from N to P is endothermic.C. The energy change from M to N is endothermic and the energy change from N to P is endothermic.D. The energy change from M to N is endothermic and the energy change from M to P is endothermic.


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END OF SECTION A

Question 30Thediagrambelowshowsthebasicset-upofanelectroplatingcell.

battery

Electrode ZPt electrode

electroplating solution

beaker

Initiallythecellissetupwithalead,Pb,electrodeasElectrodeZand1.0Mleadnitrate,Pb(NO3)2,astheelectroplatingsolution.Thecellrunsforasettimeandcurrent,with1.0gofPbdepositedontoElectrodeZ.Foursubsequentelectroplatingcellsaresetup,eachcontainingaplatinum,Pt,electrode,adifferentElectrodeZandanappropriate1.0Melectroplatingsolution.ThesefourelectroplatingcellsareoperatedforthesametimeandatthesamecurrentastheoriginalPbelectroplatingcell.WhichcombinationofElectrodeZandelectroplatingsolutionwouldbeexpectedtodepositmoremetalbymassontoElectrodeZthantheoriginalPbelectroplatingcell?

Electrode Z Electroplating solution

A. chromium,Cr 1.0MCr(NO3)3

B. silver,Ag 1.0MAgNO3

C. gold,Au 1.0MAuCl3

D. tin,Sn 1.0MSnSO4


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TURN OVER

CONTINUES OVER PAGE


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SECTION B – Question 1–continued

Question 1 (8marks)Industrially,ethanol,C2H5OH,ismadebyeitheroftwomethods.Onemethodusesethene,C2H4,whichisderivedfromcrudeoil.Theothermethodusesasugar,suchassucrose,C12H22O11,andyeast,inaqueoussolution.TheproductionofC2H5OHfromC12H22O11andyeastproceedsaccordingtotheequation

C12H22O11(aq)+H2O(l)→4C2H5OH(aq)+4CO2(g)

a. Determinethemass,ingrams,ofpureC2H5OHthatwouldbeproducedfrom1.250kgofC12H22O11 dissolvedinwater.

M(C12H22O11)=342gmol–1 2marks

b. i. Completethereactionbywritingtheformulaforthereactantintheboxprovidedbelow. 1mark

C2H4(g) + C2H5OH(g)catalyst

ii. Classifythistypeofreaction. 1mark

SECTION B

Instructions for Section BAnswerallquestionsinthespacesprovided.Writeusingblueorblackpen.Givesimplifiedanswerstoallnumericalquestions,withanappropriatenumberofsignificantfigures;unsimplifiedanswerswillnotbegivenfullmarks.Showallworkinginyouranswerstonumericalquestions;nomarkswillbegivenforanincorrectanswerunlessitisaccompaniedbydetailsoftheworking.Ensurechemicalequationsarebalancedandthattheformulasforindividualsubstancesincludeanindicationofstate,forexample,H2(g),NaCl(s).Unlessotherwiseindicated,thediagramsinthisbookarenotdrawntoscale.


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SECTION B – continuedTURN OVER

c. C2H5OHcanbeconvertedintoethanoicacid,CH3COOH,inthepresenceofReagentX.

WritetheformulaforReagentXintheboxprovidedbelow. 1mark

C2H5OH CH3COOH

Reagent X

d. CH3COOHcanbeusedintheproductionofesters.

i. WriteabalancedchemicalequationforthereactionofCH3COOHwithpropan-1-olusing semi-structuralformulasforallorganiccompounds. 2marks

ii. WritetheIUPACnamefortheesterproductoftheequationwritteninpart d.i. 1mark


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Question 2 (9marks)Avehiclethatispoweredbyadieselengineisabletouseeitherpetrodieselorbiodieselasafuel.Petrodieselandbiodieselarenotpuresubstances,butareamixtureofmolecules.Ingeneral,petrodieselconsistsofmoleculesthatareshorterinlength,onaverage,thanthosefoundinbiodiesel.Biodieselcontainsmoleculesthatincludefunctionalgroups.Thetablebelowlistssomeofthepropertiesofthetwofuels.

Fuel Major component

Energy content (MJ/kg)

CO2 emission (kg CO2/kg of fuel)

petrodiesel C12H26 43 3.17

biodiesel C19H32O2 38 2.52

a. Describeandexplainthedifferenceinviscosity,underthesameconditions,ofthetwofuelsandhowthiswouldaffecttheflowofeachfuel. 3marks


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b. Assumethatcombustionoccursinanunlimitedsupplyofoxygenforeachofthefollowingcalculations.

Usingthedatafromthetableonpage18

i. calculatethenumberoflitresofbiodieselthatarerequiredtobeburnttoproducethesameamountofenergyas2.5kgofpetrodiesel

density(biodiesel)=0.89kgL–1 3marks

ii. calculatethemassofcarbondioxide,CO2,thatwouldbeproducedfrom3.91kgofbiodiesel. 1mark

c. Insomecircumstances,thereisalimitedsupplyofoxygen.

Writethebalancedchemicalequationforthecombustionreactionofthemajorcomponentofbiodiesel,C19H32O2,wherecarbonmonoxide,CO,istheonlyproductcontainingcarbon. 2marks


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SECTION B – continued

Question 3 (10marks)Livercellscanstoreexcessglucose.

a. i. Namethepolysaccharidethatisusedtostoreexcessglucoseintheliver. 1mark

ii. Namethebondconnectingtwoglucoseunitsinthepolysaccharidenamedinpart a.i. 1mark

Glucagonisapeptidehormonethatworkswithinsulintohelpregulatebloodglucoselevels.Glucagonactstoincreasebloodglucoselevelsthroughtargetedactiononthepolysaccharidestoredintheliver.Glucagonconsistsofachainof29aminoacids,thesequenceofwhichisgivenbelow,andfoldstoformashortalpha-helix.

H2N-His-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Lys-Tyr-Leu-Asp-Ser-Arg-Arg-Ala-Gln-Asp-Phe-Val-Gln-Trp-Leu-Met-Asn-Thr-COOH

b. i. Drawadiagramofthestructureofthesectionoftheglucagonpeptideshownintheboxintheaminoacidsequenceabove. 3marks

ii. Describethebondingthatisfoundintheprimaryandsecondarystructuresoftheglucagonmolecule. 3marks

c. Explainwhytheaminoacidsserineandglutaminearenotneededinthehumandiet,whereashistidineandthreonineareneeded. 2marks


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Question 4 (8marks)Sulfurtrioxide,SO3,ismadebythereactionofsulfurdioxide,SO2,andoxygen,O2,inthepresenceofacatalyst,accordingtotheequationbelow.

2SO2(g)+O2(g)⇌2SO3(g) ΔH<0

Inaclosedsysteminthepresenceofthecatalyst,thereactionquicklyachievesequilibriumat1000K.

a. Amixtureof2.00molofSO2(g)and2.00molofO2(g)wasplacedina4.00Levacuated,sealedvesselandkeptat1000Kuntilequilibriumwasreached.Atequilibrium,thevesselwasfoundtocontain1.66molofSO3(g).

Calculatetheequilibriumconstant,Kc,at1000K. 4marks

b. AmanufacturerofSO3investigateschangestothereactionconditionsusedinpart a.inordertoincreasethepercentageyieldoftheproductinaclosedsystem,wherethevolumemaybechanged,ifrequired.

WhatchangeswouldthemanufacturermaketothetemperatureandvolumeofthesysteminordertoincreasethepercentageyieldofSO3?Justifyyouranswer. 4marks


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SECTION B – Question 5 – continued

Question 5 (9 marks)There are a number of structural isomers for the molecular formula C3H6O. Three of these are propanal, propanone and prop-2-en-1-ol.The skeletal structure for the aldehyde propanal is as follows.

O

a. i. Write the semi-structural formula for the ketone isomer propanone. 1 mark

ii. Draw the structural formula for the isomer prop-2-en-1-ol in the space provided below. 1 mark


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SECTION B – Question 5 – continuedTURN OVER

b. The mass spectrum below was produced by one of the three named isomers of C3H6O.

100

80

60

40

20

010 15 20 25 30 35 40 45

m/z50 55 60 65 70 75

relativeintensity


i. Identify the fragment at 29 m/z. 1 mark

ii. Name the isomer of C3H6O that produced this spectrum and justify your answer. 3 marks


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c. Consider the 13C NMR and 1H NMR spectra below.

13C NMR spectrum

ppm200220 180 160 140 120 100 80 60 40 20 0


1H NMR spectrum

ppm10 9 8 7 6 5 4 3 2 1 0



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Identify which one of the three named isomers of C3H6O produced the NMR spectra on page 24. Justify your answer by referencing both spectra. 3 marks


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Question 6(8marks)Submarinesoperatebothonthesurfaceandunderwater.Whenoperatingunderwater,thesubmarineactsasaclosedsystem,wherethereisnointeractionwiththeatmosphere.Mosttypesofsubmarinesusebothbatteriesanddieselenginestoprovidetheirenergyrequirements.Anewtypeofsubmarineusesprotonexchangemembrane(PEM)fuelcellsanddieselengines.BelowisadiagramofaPEMfuelcell.

load

air, containing oxygen (O2), in

hydrogen (H2)gas in

anode cathode

electrolyte

a. i. Statethefunctionoftheelectrolyteinafuelcell. 1mark

ii. WritethebalancedoverallredoxreactionthatoccursinthisPEMfuelcell. 1mark

iii. Givetwosafetyconsiderationsforthesafestorageofhydrogen,H2,gasonasubmarine. 2marks


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b. i. StatetwoadvantagesofusingaPEMfuelcellcomparedtoadieselenginewhenasubmarineisunderwater. 2marks

ii. MostsubmarinesgeneratemoreH2gasfortheirfuelcellswhentravellingonthesurface.

ExplainhowtheH2gascouldbegenerated. 2marks


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Question 7 (10marks)Atableoffattyacidsandmeltingpointsisshownbelow.

Fatty acid Melting point (°C)

palmitic 63

stearic 70

oleic 16

linoleic –5

a. Withreferencetotheirstructureandbonding,explainthedifferenceinmeltingpointsbetween 4marks

• palmiticandstearicacids

• stearicandlinoleicacids.


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b. Aparticulartriglyceridefoundinbeef,CompoundA,containsthreedifferentfattyacidchains:palmitic,stearicandoleic.CompoundAundergoeshydrolysisinthehumanbodybeforeitsnutrientscanbeabsorbed.Thereactionpathwaybelowrepresentsthisreaction.

lipase co-lipase

C15H31COOHC17H35COOHC17H33COOH

H

C

C

C

H

H

H

H

+

Compound A Compound B

+

Compound C

i. CompletethestructureofCompoundAintheboxprovided. 2marks

ii. WritetheformulaofCompoundBanditscorrectstoichiometricratiointheboxprovided. 1mark

iii. Drawthestructuralformulaoftheproductmolecule,CompoundC,intheboxprovided. 1mark

c. Lipaseandco-lipaseworktogethertocatalysethereactioninpart b.

Describehowenzymesandcoenzymesinteracttocatalyseareaction. 2marks


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Question 8 (9 marks)Fluorine, F2, gas is the most reactive of all non-metals. Anhydrous liquid hydrogen fluoride, HF, can be electrolysed to produce F2 and hydrogen, H2, gases. Potassium fluoride, KF, is added to the liquid HF to increase electrical conductivity. The equation for the reaction is

2HF(l) → F2(g) + H2(g)

F2 is used to make a range of chemicals, including sulfur hexafluoride, SF6, an excellent electrical insulator, and xenon difluoride, XeF2, a strong fluorinating agent.The diagram below shows an electrolytic cell used to prepare F2 gas.

ironelectrode

carbonelectrode

HF(l) K+ F–(HF) (HF)

electricity supply

H2(g)HF(l) top-up

diaphragm

gas collector gas collector

F2(g)

Liquid HF, like water, is an excellent solvent for ionic compounds. In the same way that water molecules in an aqueous solution form the ions K+(aq) and F–(aq), when KF is dissolved in HF, the K+ and F– ions form ions that are written as K+

(HF) and F–(HF).

a. Label the polarities of each electrode in the circles provided on the diagram above. 1 mark

b. Write the equation for the half-reaction occurring at the anode. 1 mark

c. Suggest why the diaphragm, shown in the diagram above, is important for the safe operation of the electrolytic cell. 1 mark


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d. Explainwhythecarbonelectrodecannotbereplacedwithanironelectrode. 3marks

e. CalculatethevolumeofF2gas,measuredatstandardlaboratoryconditions(SLC),thatwouldbeproducedwhenacurrentof1.50Aispassedthroughthecellfor2.00hours. 3marks


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Question 9 (13marks)Agroupofstudentsdesignedandcarriedoutanexperimenttoinvestigateiftartaricacid,C4H6O6,thatwasboughtcommerciallyis99%pure,asclaimedbythemanufacturer.TheexperimentinvolvedtitratingC4H6O6withsodiumhydroxide,NaOH,solution,calculatingthepercentagepurityofC4H6O6andcomparingtheexperimentalvaluetothemanufacturer’sstatedvalue.Partofthereportsubmittedbyoneofthestudentsisshownbelow.

ResearchTartaricacidisadiproticacidthatoccursnaturallyingrapesandotherfruit.

Skeletal diagram for C4H6O6

O

OO

O

O

O

H

H

HH

Equation for reaction C4H6O6(aq)+2NaOH(aq)→Na2C4H4O6(aq)+2H2O(l)

Aim Todeterminethepercentagepurityofthecommercialsampleoftartaricacidbytitrationtoverifythestatedvalueof99.0%

Calculations of predicted titre, in mL[C4H6O6]solution=30/150×1/0.50=0.40molL–1

n(C4H6O6)in10.00mL=0.40×10/1000=0.0040moln(NaOH)=2×n(C4H6O6)=0.0080molV(NaOH)titre=0.0080/0.5=0.016L=16.00mL

Method

Part A – Preparation of tartaric acid solution1. Purchasetartaricacid,C4H6O6,powder.2. PrepareasolutionofC4H6O6byaccuratelymeasuring30.0gofthepowder,placingitina500.00mL

volumetricflaskandthenmakingitupto500.00mLwithde-ionisedwater.

Part B – Titration1. Collectstocksolutionof0.5Msodiumhydroxide,NaOH,andusethistofillaburette.2. Delivera10.00mLaliquotofC4H6O6solutionintoaconicalflask.Addfourdropsofphenolphthalein

indicator.3. Carefullytitrate0.5MNaOHintotheC4H6O6solutionuntilapermanentpinkcolourremains.4. Recordthevolumeofthetitre.5. Repeatthetitrationuntilconcordanttitresareobtained.


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SECTION B – Question 9–continuedTURN OVER

Results

Trial number Volume of aliquot of C4H6O6 (mL)

Volume of titre of NaOH (mL)

1 10.00 14.96

2 10.00 14.81

3 10.00 14.70

4 10.00 14.76

5 10.00 14.79

Calculationsaveragetitre=(14.81+14.76+14.79)/3=14.79mLn(NaOH)=0.5×0.01479mol=0.00749n(C2H6O6)=1/2×n(NaOH)=0.00749/2=0.00370molin10.00mLofC4H6O6solution

Percentage purity%purityofC4H6O6=actual n/predictedn×100=0.0037/0.0040×100=92.5%

ConclusionThroughdirecttitrationoftartaricacidwithsodiumhydroxidesolution,thepercentagepurityofthecommercialsupplyoftartaricacidwasfoundtobe92.5%.Thisislessthanthestatedvalueof99%purity.Consequently,themanufacturer’sclaimiswrong.

a. Nametheindependentvariableinthisexperiment. 1mark

b. Identifyacontrolledvariableinthisexperimentandstatewhyitisimportantforthisvariabletobecontrolled. 2marks


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c. Is the value the student used for the average titre in the ‘Calculations’ section on page 33 appropriate? Explain your reasoning. 2 marks

d. Consider the method undertaken by the student in this experiment to determine the percentage purity of C4H6O6 powder. Identify how specific steps in the method affect the accuracy and reliability of the data. 4 marks

e. Identify a limitation of the student’s conclusion. How could this limitation be addressed? 2 marks


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f. Thematerialsafetydatasheet(MSDS)forC4H6O6powderincludesthefollowingstatement: ‘Warning!Thisproductcauseseye,skinandrespiratorytractirritation.’

Apartfromalaboratorycoat,whatpersonalprotectiveequipment(PPE)shouldbeusedbythestudentsineachofthefollowingsituations? 2marks

• PreparingtheC4H6O6solution

• Conductingthetitration


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Question 10 (6marks)TheplanetMarshasasimilardayandnightcycletoEarthandadayonMarslastsabout24hrs40min.TheatmosphericpressureonMarsislessthan1%ofEarth’satmosphericpressureandover95%oftheMarsatmosphereiscarbondioxide.Water,asice,isfoundinabundancejustbelowthesurfaceinseverallocations.Theaveragetemperatureis–55°C.Thesurfacetemperaturemayreach20°Cattheequatorandaslowas–153°Catthepoles.AcompanyispreparingaproposaltosetupacolonyonMarsforagovernmentspaceagency.Amajorcomponentoftheplanningstageisensuringthattheenergyneededtosustainthecolonyisavailable.ThecolonyonMarsisexpectedtobecomeself-sufficientinenergyaftersixmonths.Thecompanyhasidentifiedtheneedtogenerateusableenergyintheshorttermandoveralongertimeperiod.Onesuggestionisusingbiofuelstogenerateusableenergy.BiologicalorganismswouldbetransportedfromEarth,alongwiththeequipmentneededtogeneratebiogas,bioethanolandbiodiesel.

a. Usingthechemistryyoustudiedthisyearandtheinformationabove,evaluatethefeasibilityofthissuggestionformeetingtheenergyneedsofacolonyonMars. 4marks


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END OF QUESTION AND ANSWER BOOK

b. Analternativesuggestionistousebatteriesthathavetheadvantageofbeingrechargedusingsolarenergy.

Stateoneotheradvantageofthissuggestion.Giveareasonforyouranswer. 2marks

Instructions

This data book is provided for your reference. A question and answer book is provided with this data book.

Students are NOT permitted to bring mobile phones and/or any other unauthorised electronic devices into the examination room.

CHEMISTRYWritten examination

DATA BOOK

© VICTORIAN CURRICULUM AND ASSESSMENT AUTHORITY 2017

Victorian Certificate of Education 2017

CHEMISTRY DATA BOOK 2

Table of contents Page

1. Periodic table of the elements 3

2. Electrochemical series 4

3. Chemical relationships 5

4. Physical constants and standard values 5

5. Unit conversions 6

6. Metric(includingSI)prefixes 6

7. Acid-base indicators 6

8. Representations of organic molecules 7

9. Formulas of some fatty acids 7

10. Formulas of some biomolecules 8–9

11. Heats of combustion of common fuels 10

12. Heats of combustion of common blended fuels 10

13. Energy content of food groups 10

14. Characteristic ranges for infra-red absorption 11

15. 13C NMR data 11

16. 1H NMR data 12–13

17. 2-aminoacids(α-aminoacids) 14–15

3 CHEMISTRY DATA BOOK

TURN OVER

1. P

erio

dic t

able

of t

he el

emen

ts

1 H

1.0

hydr

ogen

2 He

4.0

heliu

m

3 Li

6.9

lithi

um

4 Be

9.0

bery

llium

5 B

10.8

bo

ron

6 C

12.0

ca

rbon

7 N

14.0

ni

troge

n

8 O

16.0

oxygen

9 F 19.0

fluorine

10

Ne

20.2

ne

on

11

Na

23.0

so

dium

12

Mg

24.3

m

agne

sium

13

Al

27.0

al

umin

ium

14

Si

28.1

si

licon

15

P 31.0

ph

osph

orus

16

S 32.1

su

lfur

17

Cl

35.5

ch

lorin

e

18

Ar

39.9

ar

gon

19

K

39.1

po

tass

ium

20

Ca

40.1

ca

lciu

m

21

Sc

45.0

sc

andi

um

22

Ti

47.9

tit

aniu

m

23

V

50.9

va

nadi

um

24

Cr

52.0

ch

rom

ium

25

Mn

54.9

m

anga

nese

26

Fe

55.8

iro

n

27

Co

58.9

co

balt

28

Ni

58.7

ni

ckel

29

Cu

63.5

co

pper

30

Zn

65.4

zi

nc

31

Ga

69.7

ga

llium

32

Ge

72.6

ge

rman

ium

33

As

74.9

ar

seni

c

34

Se

79.0

se

leni

um

35

Br

79.9

br

omin

e

36

Kr

83.8

kr

ypto

n

37

Rb

85.5

ru

bidi

um

38

Sr

87.6

st

ront

ium

39

Y

88.9

yt

trium

40

Zr

91.2

zi

rcon

ium

41

Nb

92.9

ni

obiu

m

42

Mo

96.0

m

olyb

denu

m

43

Tc

(98)

te

chne

tium

44

Ru

101.

1 ru

then

ium

45

Rh

102.

9 rh

odiu

m

46

Pd

106.

4 pa

lladi

um

47

Ag

107.

9 si

lver

48

Cd

112.

4 ca

dmiu

m

49

In

114.

8 in

dium

50

Sn

118.

7 tin

51

Sb

121.

8 an

timon

y

52

Te

127.

6 te

lluriu

m

53

I 12

6.9

iodi

ne

54

Xe

131.

3 xenon

55

Cs

132.

9 ca

esiu

m

56

Ba

137.

3 ba

rium

57–7

1 la

ntha

noid

s

72

Hf

178.

5 ha

fniu

m

73

Ta

180.

9 ta

ntal

um

74

W

183.

8 tu

ngst

en

75

Re

186.

2 rh

eniu

m

76

Os

190.

2 os

miu

m

77

Ir

192.

2 iri

dium

78

Pt

195.

1 pl

atin

um

79

Au

197.

0 go

ld

80

Hg

200.

6 m

ercu

ry

81

Tl

204.

4 th

alliu

m

82

Pb

207.

2 le

ad

83

Bi

209.

0 bi

smut

h

84

Po

(210

) po

loni

um

85

At

(210

) as

tatin

e

86

Rn

(222

) ra

don

87

Fr

(223

) fr

anci

um

88

Ra

(226

) ra

dium

89–1

03

actin

oids

104

Rf

(261

) ru

ther

ford

ium

105

Db

(262

) du

bniu

m

106

Sg

(266

) se

abor

gium

107

Bh

(264

) bo

hriu

m

108

Hs

(267

) ha

ssiu

m

109

Mt

(268

) m

eitn

eriu

m

110

Ds

(271

) da

rmst

adtiu

m

111

Rg

(272

) ro

entg

eniu

m

112

Cn

(285

) co

pern

iciu

m

113

Nh

(280

) ni

honi

um

114

Fl

(289

) flerovium

115

Mc

(289

) m

osco

vium

116

Lv

(292

) liv

erm

oriu

m

117

Ts

(294

) te

nnes

sine

118

Og

(294

) og

anes

son

57

La

138.

9 la

ntha

num

58

Ce

140.

1 ce

rium

59

Pr

140.

9 pr

aseo

dym

ium

60

Nd

144.

2 ne

odym

ium

61

Pm

(145

) pr

omet

hium

62

Sm

150.

4 sa

mar

ium

63

Eu

152.

0 eu

ropi

um

64

Gd

157.

3 ga

dolin

ium

65

Tb

158.

9 te

rbiu

m

66

Dy

162.

5 dy

spro

sium

67

Ho

164.

9 ho

lmiu

m

68

Er

167.

3 er

bium

69

Tm

16

8.9

thul

ium

70

Yb

173.

1 yt

terb

ium

71

Lu

175.

0 lu

tetiu

m

89

Ac

(227

) ac

tiniu

m

90

Th

232.

0 th

oriu

m

91

Pa

231.

0 pr

otac

tiniu

m

92

U

238.

0 ur

aniu

m

93

Np

(237

) ne

ptun

ium

94

Pu

(244

) pl

uton

ium

95

Am

(2

43)

amer

iciu

m

96

Cm

(2

47)

curiu

m

97

Bk

(247

) be

rkel

ium

98

Cf

(251

) ca

lifor

nium

99

Es

(252

) ei

nste

iniu

m

100

Fm

(257

) fe

rmiu

m

101

Md

(258

) m

ende

levi

um

102

No

(259

) no

beliu

m

103

Lr

(262

) la

wre

nciu

m

The

valu

e in

bra

cket

s ind

icat

es th

e m

ass n

umbe

r of t

he lo

nges

t-liv

ed is

otop

e.

79

Au

197.

0 go

ld

atom

ic n

umbe

r

rela

tive

atom

ic m

ass

sym

bol o

f ele

men

t

nam

e of

ele

men

t


2. Electrochemical series

Reaction Standard electrode potential (E0) in volts at 25 °C

F2(g) + 2e– ⇌ 2F–(aq) +2.87

H2O2(aq) + 2H+(aq) + 2e– ⇌ 2H2O(l) +1.77

Au+(aq) + e– ⇌ Au(s) +1.68

Cl2(g) + 2e– ⇌ 2Cl–(aq) +1.36

O2(g) + 4H+(aq) + 4e– ⇌ 2H2O(1) +1.23

Br2(l) + 2e– ⇌ 2Br–(aq) +1.09

Ag+(aq) + e– ⇌ Ag(s) +0.80

Fe3+(aq) + e– ⇌ Fe2+(aq) +0.77

O2(g) + 2H+(aq) + 2e– ⇌ H2O2(aq) +0.68

I2(s) + 2e– ⇌ 2I–(aq) +0.54

O2(g) + 2H2O(l) + 4e– ⇌ 4OH–(aq) +0.40

Cu2+(aq) + 2e– ⇌ Cu(s) +0.34

Sn4+(aq) + 2e– ⇌ Sn2+(aq) +0.15

S(s) + 2H+(aq) + 2e– ⇌ H2S(g) +0.14

2H+(aq) + 2e– ⇌ H2(g) 0.00

Pb2+(aq) + 2e– ⇌ Pb(s) –0.13

Sn2+(aq) + 2e– ⇌ Sn(s) –0.14

Ni2+(aq) + 2e– ⇌ Ni(s) –0.25

Co2+(aq) + 2e– ⇌ Co(s) –0.28

Cd2+(aq) + 2e– ⇌ Cd(s) –0.40

Fe2+(aq) + 2e– ⇌ Fe(s) –0.44

Zn2+(aq) + 2e– ⇌ Zn(s) –0.76

2H2O(l) + 2e– ⇌ H2(g) + 2OH–(aq) –0.83

Mn2+(aq) + 2e– ⇌ Mn(s) –1.18

Al3+(aq) + 3e– ⇌ Al(s) –1.66

Mg2+(aq) + 2e– ⇌ Mg(s) –2.37

Na+(aq) + e– ⇌ Na(s) –2.71

Ca2+(aq) + 2e– ⇌ Ca(s) –2.87

K+(aq) + e– ⇌ K(s) –2.93

Li+(aq) + e– ⇌ Li(s) –3.04


TURN OVER

3. Chemical relationships

Name Formula

number of moles of a substance n mM

n cV n VVm

= = =; ;

universal gas equation pV = nRT

calibration factor (CF) for bomb calorimetry CF = VItT∆

heat energy released in the combustion of a fuel q = mc∆T

enthalpy of combustion ∆H qn

=

electric charge Q = It

number of moles of electrons n e QF

( )− =

% atom economymolar mass of desired product

molar mass of all reactants×

10001

% yieldactual yield

theoretical yield×

1001

4. Physical constants and standard values

Name Symbol Value

Avogadro constant NA or L 6.02 × 1023 mol–1

charge on one electron (elementary charge) e –1.60 × 10–19 C

Faraday constant F 96 500 C mol–1

molar gas constant R 8.31 J mol–1 K–1

molar volume of an ideal gas at SLC (25 °C and 100 kPa)

Vm 24.8 L mol–1

specificheatcapacityofwater c 4.18 kJ kg–1 K–1 or 4.18 J g–1 K–1

density of water at 25 °C d 997 kg m–3 or 0.997 g mL–1


5. Unit conversions

Measured value Conversion

0 °C 273 K

100 kPa 750 mm Hg or 0.987 atm

1 litre (L) 1 dm3 or 1 × 10–3 m3 or 1 × 103 cm3 or 1 × 103 mL

6. Metric (including SI) prefixes

Metric (including SI)

prefixes

Scientific notation Multiplying factor

giga (G) 109 1 000 000 000

mega (M) 106 1 000 000

kilo (k) 103 1000

deci (d) 10–1 0.1

centi (c) 10–2 0.01

milli (m) 10–3 0.001

micro (μ) 10–6 0.000001

nano (n) 10–9 0.000000001

pico (p) 10–12 0.000000000001

7. Acid-base indicators

Name pH range Colour change from lower pH to higher pH in range

thymol blue (1st change) 1.2–2.8 red → yellow

methyl orange 3.1– 4.4 red → yellow

bromophenol blue 3.0– 4.6 yellow → blue

methyl red 4.4– 6.2 red → yellow

bromothymol blue 6.0–7.6 yellow → blue

phenol red 6.8–8.4 yellow → red

thymol blue (2nd change) 8.0–9.6 yellow → blue

phenolphthalein 8.3–10.0 colourless → pink


TURN OVER

8. Representations of organic moleculesThefollowingtableshowsdifferentrepresentationsoforganicmolecules,usingbutanoicacidasanexample.

Formula Representation

molecular formula C4H8O2

structural formula

C

H

H

C

H

H

C

H

H

C

HO

O

H

semi-structural (condensed) formula CH3CH2CH2COOH or CH3(CH2)2COOH

skeletal structure O

OH

9. Formulas of some fatty acids

Name Formula Semi-structural formula

lauric C11H23COOH CH3(CH2)10COOH

myristic C13H27COOH CH3(CH2)12COOH

palmitic C15H31COOH CH3(CH2)14COOH

palmitoleic C15H29COOH CH3(CH2)4CH2CH=CHCH2 (CH2)5CH2COOH

stearic C17H35COOH CH3(CH2)16COOH

oleic C17H33COOH CH3(CH2)7CH=CH(CH2)7COOH

linoleic C17H31COOH CH3(CH2)4(CH=CHCH2)2(CH2)6COOH

linolenic C17H29COOH CH3CH2(CH=CHCH2)3(CH2)6COOH

arachidic C19H39COOH CH3(CH2)17CH2COOH

arachidonic C19H31COOH CH3(CH2)4(CH=CHCH2)3CH=CH(CH2)3COOH


10. Formulas of some biomolecules

C

C

C

H

H

OH

OH

OH

H

H

H

glycerol

sucrose

OH OH

OH OHHO

O O

O

CH2OH CH2OH

CH2OH

vitamin C (ascorbic acid)

O

OH

O

HO

CH

OH

CH2

HO

vitamin D2 (ergocalciferol)HO

CHCH

CHCH3

CH2

H3C CH3

CH3

CHCH

CHCH3

CH

HO

β-fructose

OH

OH

OCH2OH

CH2OH

vitamin D3 (cholecalciferol)HO

CHCH

CH3

CH2

CHH3C CH3CH2

CH2

CHCH3

CH2

α-glucose

OH

OHHO

O

OH

CH2OH

lactose

OH

OH

HO O O

CH2OH

OH

OHOH

O

CH2OH


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OH

OH

n

cellulose

OH

OH

O

O

O

O O

CH2OH

CH2OH

OH

OH

O

O O

CH2OH

OH

OH

O

O

CH2OH

OH

OH

O

O

CH2

OH

OH

O

O

CH2OH

amylopectin (starch)

O

OH

OH

O

O O

CH2OH

OH

OH

O

O

CH2OH

OH

OH

O

O

CH2OH

amylose (starch)

n

O

HO

O

O

O

N CH3

aspartame

H

H2N


11. Heats of combustion of common fuelsThe heats of combustion in the following table are calculated at SLC (25 °C and 100 kPa) with combustion products being CO2 and H2O. Heat of combustion may be defined as the heat energy released when a specified amount of a substance burns completely in oxygen and is, therefore, reported as a positive value, indicating a magnitude. Enthalpy of combustion, ∆H, for the substances in this table would be reported as negative values, indicating the exothermic nature of the combustion reaction.

Fuel Formula State Heat of combustion (kJ g–1)

Molar heat of combustion (kJ mol–1)

hydrogen H2 gas 141 282

methane CH4 gas 55.6 890

ethane C2H6 gas 51.9 1560

propane C3H8 gas 50.5 2220

butane C4H10 gas 49.7 2880

octane C8H18 liquid 47.9 5460

ethyne (acetylene) C2H2 gas 49.9 1300

methanol CH3OH liquid 22.7 726

ethanol C2H5OH liquid 29.6 1360

12. Heats of combustion of common blended fuelsBlended fuels are mixtures of compounds with different mixture ratios and, hence, determination of a generic molar enthalpy of combustion is not realistic. The values provided in the following table are typical values for heats of combustion at SLC (25 °C and 100 kPa) with combustion products being CO2 and H2O. Values for heats of combustion will vary depending on the source and composition of the fuel.

Fuel State Heat of combustion (kJ g–1)

kerosene liquid 46.2

diesel liquid 45.0

natural gas gas 54.0

13. Energy content of food groups

Food Heat of combustion (kJ g–1)

fats and oils 37

protein 17

carbohydrate 16


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14. Characteristic ranges for infra-red absorption

Bond Wave number (cm–1)

Bond Wave number (cm–1)

C–Cl (chloroalkanes) 600–800 C=O (ketones) 1680–1850

C–O (alcohols, esters, ethers) 1050–1410 C=O (esters) 1720–1840

C=C (alkenes) 1620–1680 C–H (alkanes, alkenes, arenes) 2850–3090

C=O (amides) 1630–1680 O–H (acids) 2500–3500

C=O (aldehydes) 1660–1745 O–H (alcohols) 3200–3600

C=O (acids) 1680–1740 N–H (amines and amides) 3300–3500

15. 13C NMR dataTypical 13C shift values relative to TMS = 0These can differ slightly in different solvents.

Type of carbon Chemical shift (ppm)

R–CH3 8–25

R–CH2–R 20– 45

R3–CH 40–60

R4–C 36– 45

R–CH2–X 15–80

R3C–NH2, R3C–NR 35–70

R–CH2–OH 50–90

RC CR 75–95

R2C=CR2 110–150

RCOOH 160–185

OR

ROC

165–175

OR

HC

190–200

R2C=O 205–220


16. 1H NMR dataTypical proton shift values relative to TMS = 0These can differ slightly in different solvents. The shift refers to the proton environment that is indicated in bold letters in the formula.

Type of proton Chemical shift (ppm)

R–CH3 0.9–1.0

R–CH2–R 1.3–1.4

RCH=CH–CH3 1.6–1.9

R3–CH 1.5

or CH3

ORC

OCH3

NHR

CO

2.0

CH3R

C

O

2.1–2.7

R–CH2–X (X = F, Cl, Br or I) 3.0– 4.5

R–CH2–OH, R2–CH–OH 3.3– 4.5

R

NHCH2R

CO

3.2

R—O—CH3 or R—O—CH2R 3.3–3.7

O C

O

CH32.3

R

OCH2R

CO

3.7– 4.8

R–O–H 1–6(varies considerably under different conditions)

R–NH2 1–5

RHC CHR 4.5–7.0

OH 4.0–12.0


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Type of proton Chemical shift (ppm)

H 6.9–9.0

R

NHCH2R

CO

8.1

R

H

CO

9.4 –10.0

RH

CO

O9.0–13.0


17. 2-amino acids (α-amino acids)Thetablebelowprovidessimplifiedstructurestoenablethedrawingofzwitterions,theidentificationofproducts of protein hydrolysis and the drawing of structures involving condensation polymerisation of amino acid monomers.

Name Symbol Structure

alanine Ala

H2N CH COOH

CH3

arginine Arg

H2N CH COOH

CH2 CH2 CH2 NH

NH

C NH2

asparagine Asn

H2N CH COOH

CH2

O

C NH2

aspartic acid Asp

H2N CH COOH

CH2 COOH

cysteine Cys

H2N CH COOH

CH2 SH

glutamic acid Glu

H2N CH COOH

CH2 CH2 COOH

glutamine Gln

H2N CH COOH

CH2 CH2

O

C NH2

glycine Gly H2N CH2 COOH

histidine His

H2N CH COOH

CH2 NH

N

isoleucine Ile

H2N CH COOH

CH3 CH CH2 CH3


END OF DATA BOOK

Name Symbol Structure

leucine Leu

H2N CH COOH

CH2

CH3 CH CH3

lysine Lys

H2N CH COOH

CH2 CH2 CH2 CH2 NH2

methionine Met

H2N CH COOH

CH2 CH2 S CH3

phenylalanine Phe

H2N CH

CH2

COOH

proline Pro COOH

HN

serine Ser

H2N CH COOH

CH2 OH

threonine Thr

H2N CH COOH

CH3 CH OH

tryptophan Trp

H2N CH

CH2

COOH

HN

tyrosine Tyr OH

H2N CH

CH2

COOH

valine Val

H2N CH COOH

CH3 CH CH3

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2017 Chemistry Written examination - vcaa.vic.edu.au · PDF filemoves the chemical equilibrium of a reaction in the forward ... , which one of the following fatty acids is likely to