2020 chemistry written examination

CHEMISTRYWritten examination

Monday 23 November 2020 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• Questionandanswerbookof39pages• 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.

©VICTORIANCURRICULUMANDASSESSMENTAUTHORITY2020

SUPERVISOR TO ATTACH PROCESSING LABEL HEREVictorian Certificate of Education 2020

STUDENT NUMBER

Letter

2020CHEMISTRYEXAM 2

SECTION A – continued

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eaQuestion 1

GlycogenbreaksdownintoA. glycerol.B. aminoacids.C. triglycerides.D. monosaccharides.

Question 2UsinglargesamplesizesinanexperimentincreasesA. reliability.B. precision.C. validity.D. uncertainty.

SECTION A – Multiple-choice questions

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

3 2020CHEMISTRYEXAM

SECTION A – continuedTURN OVER

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Question 3Adiagramofanelectrochemicalcellisshownbelow.

V

Q S

e– e–

P R

Whichofthefollowinggivesthecorrectcombinationoftheelectrodeintheoxidationhalf-cellandtheelectrolyteinthereductionhalf-cell?

Electrode (oxidation half-cell)

Electrolyte (reduction half-cell)

A. S P

B. S R

C. Q R

D. Q P

2020CHEMISTRYEXAM 4


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Question 4

HH

HH

H

HH

H

HH

H

HH

N

CC

CC

CO

WhatistheIUPACnameofthemoleculeshownabove?A. 3-hydroxy-3-ethyl-propan-1-amineB. 3-amino-1-methylpropan-1-olC. 3-hydroxypentan-1-amineD. 1-aminopentan-3-ol

Question 5ThemetabolicprocessthatproduceswaterisA. thedigestionoffats.B. cellularrespiration.C. thehydrolysisofstarch.D. thebreakdownofproteinintoaminoacids.

Question 6Whichoneofthefollowingpairsofstatementsiscorrectforbothelectrolysiscellsandgalvaniccells?

Electrolysis cell Galvanic cell

A. Bothelectrodesarealwaysinert. Bothelectrodesarealwaysmadeofmetal.

B. Electricalenergyisconvertedtochemicalenergy.

Thevoltageofthecellisindependentoftheelectrolyteconcentration.

C. Chemicalenergyisconvertedtoelectricalenergy.

Theproductsaredependentonthehalf-cellcomponents.

D. Theproductsaredependentonthe half-cellcomponents.

Chemicalenergyisconvertedtoelectricalenergy.

5 2020CHEMISTRYEXAM


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Question 7HowmanystructuralisomershavethemolecularformulaC3H6BrCl?A. 4B. 5C. 6D. 7

Question 8Whichoneofthefollowingisthemostcorrectstatementaboutfuelcellsandsecondarycells?A. Fuelcellscanberechargedlikesecondarycells.B. Fuelcellsproducethermalenergy,whereassecondarycellsdonotproducethermalenergy.C. Theanodeinafuelcellispositive,whereastheanodeinasecondarycellisnegative.D. Fuelcellsdeliveraconstantvoltageduringtheiroperation,whereassecondarycellsreduceinvoltageasthey

discharge.

2020CHEMISTRYEXAM 6


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Use the following information to answer Questions 9 and 10.Asolutioncalorimetercontaining350mLofwaterwassetup.Thecalorimeterwascalibratedelectricallyandthegraphoftheresultsisshownbelow.

Graph of temperature versus time during electrical calibration of solution calorimeter

22

21

20

19

18

170 30 60 90 120 150

time (s)180 210 240 270 300

temperature(°C)

Thecalorimeterwascalibratedusingacurrentof2.7A,startingat60s.Thecurrentwasappliedfor180sandtheappliedvoltagewas5.4V.

Question 9Whatisthecalibrationfactorforthiscalorimeter?A. 125J°C−1

B. 820J°C−1

C. 847J°C−1

D. 875J°C−1

Question 10ThistypeofcalorimeterA. hasnoheatloss.B. canbeusedforbombcalorimetry.C. requireselectricalcalibrationinordertodeterminethecalibrationfactor.D. measuresenergychangesthatcanbemeasuredinabombcalorimeter.

7 2020CHEMISTRYEXAM


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Question 11Whichoneofthefollowingstatementsiscorrect?A. Crudeoilcanbeclassifiedasabiofuelbecauseitoriginallycomesfromplants.B. Methane,CH4,canbeclassifiedasafossilfuelbecauseithasmajorenvironmentalimpacts.C. Ethanol,CH3CH2OH,canbeclassifiedasafossilfuelbecauseitcanbeproducedfromcrudeoil.D. Hydrogen,H2,canbeclassifiedasabiofuelbecause,whenitcombusts,itdoesnotproducecarbondioxide,

CO2.

Question 12Thediagrambelowrepresentsasectionofanenzyme.

NH2

CH2

H2C

CCHN

CO

H O

H

N

O

O

C CCN

HCH3

CH2

CH2

NH2

H

C

H

H2C

H2C

ThediagramcanbedescribedasaA. secondarystructureconsistingofglutamine,glycineandlysine.B. primarystructureconsistingofasparagine,glycineandlysine.C. secondarystructureconsistingofasparagine,alanineandlysine.D. primarystructureconsistingofglutamine,alanineandlysine.

Question 13Hydrogen,H2,fuelcellsandH2-poweredcombustionenginescanbothbeusedtopowercars.ThreestatementsaboutH2fuelcellsandH2-poweredcombustionenginesaregivenbelow:I NeitherH2fuelcellsnorH2-poweredcombustionenginesproducegreenhousegases.II LessH2isrequiredperkilometretravelledwhenusinganH2-poweredcombustionenginethanwhenusing

H2fuelcells.III MoreheatperkilogramofH2isgeneratedinanH2-poweredcombustionenginethaninH2fuelcells.

Whichofthestatementsabovearecorrect?A. IIonlyB. IandIIonlyC. IIIonlyD. IandIIIonly

2020CHEMISTRYEXAM 8


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Use the following information to answer Questions 14 and 15.Themagnitudeoftheequilibriumconstant,Kc,at25°Cforthefollowingreactionis640.

N2(g)+3H2(g)⇌2NH3(g) ΔH=−92.3kJmol−1

Question 14Forthereaction

13N2(g)+H2(g)⇌

23 NH3(g),themagnitudeofKcat25°Cis

A. 9andΔH=−30.8kJmol−1

B. 213andΔH=−30.8kJmol−1

C. 640andΔH=−30.8kJmol−1

D. 640andΔH=−92.3kJmol−1

Question 15ForthereactionN2(g)+3H2(g)⇌2NH3(g)A. acatalystincreasesthenumberofcollisionsbetweenthereactants.B. therateoftheforwardreactionincreaseswhenthetemperatureincreases.C. acatalystreducestheactivationenergyoftheforwardandbackwardreactionsbythesameproportion.D. theactivationenergyoftheforwardreactionisgreaterthantheactivationenergyofthereversereaction.

9 2020CHEMISTRYEXAM


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Question 16Thefollowingtableprovidesinformationaboutthreeorganiccompounds,X,YandZ.

Compound Structural formula Molar mass (g mol–1)

Boiling point (°C)

X H H H

CH C C O

H H H

H

60 97

Y H

C C

O

O HH

H

60 118

Z H

C

H

H O C

O

H

60 ?

WhichoneofthefollowingisthebestestimatefortheboilingpointofCompoundZ?A. 31 °CB. 101°CC. 114°CD. 156°C

2020CHEMISTRYEXAM 10


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Question 17Thefollowingequationrepresentsthereactionbetweenchlorinegas,Cl2,andcarbonmonoxidegas,CO.

Cl2(g)+CO(g)⇌COCl2(g) ΔH =−108kJmol−1

Theconcentration–timegraphbelowrepresentschangestothesystem.

10 2 3 4 5time (min)

6 7 8 9 10

Cl2

CO

COCl2

concentration(M)

Whichofthefollowingidentifiesthechangestothesystemthattookplaceat1minuteandat7minutes?

1 minute 7 minutes

A. increaseintemperature increaseinvolume

B. decreaseintemperature decreaseinvolume

C. decreaseintemperature increaseinvolume

D. increaseintemperature decreaseinvolume

11 2020CHEMISTRYEXAM


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Question 18 Anexperimentwascarriedouttodeterminetheenthalpyofcombustionofpropan-1-o1.Combustionof557mgofpropan-1-o1increasedthetemperatureof150gofwaterfrom22.1°Cto40.6°C.TheenthalpyofcombustionisclosesttoA. −2742kJmol−1

B. −1208kJmol−1

C. −1250kJmol−1

D. −1540kJmol−1

Question 19Nitrogendioxide,NO2,anddinitrogentetroxide,N2O4,formanequilibriummixturerepresentedbythefollowingequation.

2NO2(g)⇌N2O4(g) ΔH=−57.2kJmol−1

brown colourless

Achangewasmadeattimet1toanequilibriummixtureofNO2andN2O4,whichachievedanewequilibriumattimet2.Agraphshowingtherateoftheforwardreactionisshownbelow.

rate offorwardreaction

t1 t2time

Whichoneofthefollowingdescribesthechangethatwasmadetotheinitialequilibriumsystemandthecolourchangethatoccurredbetweent1andt2?A. Thetemperaturewasincreasedandthecolourlightened.B. Thetemperaturewasincreasedandthecolourdarkened.C. Thetemperaturewasdecreasedandthecolourlightened.D. Thetemperaturewasdecreasedandthecolourdarkened.



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Question 20Considerthefollowingchangesthatcouldbeappliedtotheoperatingparametersforachromatogramsetuptocarryouthigh-performanceliquidchromatography(HPLC)withapolarstationaryphaseandanon-polarmobilephase:I decreasingtheviscosityofthemobilephaseII usingamoretightlypackedstationaryphaseIII usingamobilephasethatismorepolarthanthestationaryphase

WhichofthechangeswouldbemostlikelytoreducetheretentiontimeofasugarintheHPLC?A. IonlyB. IandIIIonlyC. IIIonlyD. IIandIIIonly

Question 21Theinfra-red(IR)spectrumofanorganiccompoundisshownbelow.

100

50

0

transmittance(%)

4000 3000 2000

wave number (cm–1)

1500 1000 500

Data:SDBSWeb,<https://sdbs.db.aist.go.jp>, NationalInstituteofAdvancedIndustrialScienceandTechnology

ReferringtotheIRspectrumabove,thecompoundcouldbeA. CH3CH2COOCH3

B. CH3CH2CH2CHOC. NH2CH2CH2CONH2

D. NH2CH2CH2CHOHCH3


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SECTION A–continuedTURN OVER

Question 22 Thecombustionofwhichfuelprovidesthemostenergyper100g?A. pentane(M=72gmol−1),whichreleases49097MJtonne−1

B. nitromethane(M=61gmol−1),whichreleases11.63kJg−1

C. butanol(M=74gmol−1),whichreleases2670kJmol−1

D. ethyne(M=26gmol−1),whichreleases1300kJmol−1

Use the following information to answer Questions 23 and 24.Asolutionofcitricacid,C3H5O(COOH)3,wasanalysedbytitration.25.0mLaliquotsoftheC3H5O(COOH)3solutionweretitratedagainstastandardisedsolutionof0.0250Msodiumhydroxide,NaOH.Phenolphthaleinindicatorwasusedandtheaveragetitrewasfoundtobe24.0mL.

Question 23Basedonthetitration,theconcentrationofC3H5O(COOH)3inthesolutionwasA. 8.0×10−3MB. 8.7×10−3MC. 2.6×10−2MD. 7.2×10−2M

Question 24Whichoneofthefollowingwouldhaveresultedinaconcentrationthatishigherthantheactualconcentration?A. ThepipettewasrinsedwithNaOHsolution.B. ThepipettewasrinsedwithC3H5O(COOH)3solution.C. TheconicalflaskwasrinsedwithNaOHsolution.D. TheconicalflaskwasrinsedwithC3H5O(COOH)3solution.

Question 25Petrodieselismadeupofanumberofdifferentmolecules,includingC12H26.BiodieseloftencontainsC11H22O2.WhencomparingC12H26andC11H22O2,whichoneofthefollowingstatementsiscorrect?A. C12H26hasahigherviscosityduetothedispersionforcesbetweenthemolecules.B. C12H26islesshygroscopicasithasonlydispersionforcesbetweenthemolecules.C. C11H22O2hasahigherenergycontentwhenitcombustsasitcontainsoxygenatoms.D. C11H22O2producesmorecarbondioxidepermolewhenitcombustsduetoitshighermolecularweight.



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Question 26Thefollowingreactionsoccurinaprimarycellbattery.

Zn+2OH− →ZnO+H2O+2e−

2MnO2+2e−+H2O→Mn2O3+2OH−

Whichoneofthefollowingstatementsaboutthebatteryiscorrect?A. ThereactionproducesheatandZnreactsdirectlywithMnO2.B. ThereactionproducesheatandZndoesnotreactdirectlywithMnO2.C. ThereactiondoesnotproduceheatandZnreactsdirectlywithMnO2.D. ThereactiondoesnotproduceheatandZndoesnotreactdirectlywithMnO2.

Use the following information to answer Questions 27 and 28.Theheatofcombustionofethanoicacid,C2H4O2,is−876kJmol−1andtheheatofcombustionofmethylmethanoate,C2H4O2,is−973kJmol−1.Theauto-ignitiontemperature(thetemperatureatwhichasubstancewillcombustinairwithoutasourceofignition)ofethanoicacidis485°Candtheauto-ignitiontemperatureofmethylmethanoateis449°C.

Question 27 Whichoneofthefollowingpairsiscorrect?

Compound with the lower chemical energy per mole

Compound with the lower activation energy of combustion per mole

A. ethanoicacid methylmethanoate

B. ethanoicacid ethanoicacid

C. methylmethanoate methylmethanoate

D. methylmethanoate ethanoicacid

Question 28If0.1molofethanoicacidand0.1molofmethylmethanoatewerecompletelycombustedintwoseparateclosedvesselsunderidenticalconditions,theMaxwell-BoltzmanndistributionoftheproductgasesfromthecombustionofethanoicacidwouldbeA. broaderthantheMaxwell-Boltzmanndistributionofthemethylmethanoateproductgasesandthechemical

energyoftheproductgaseswouldbeidentical.B. narrowerthantheMaxwell-Boltzmanndistributionofthemethylmethanoateproductgasesandthechemical

energyoftheproductgaseswouldbeidentical.C. broaderthantheMaxwell-Boltzmanndistributionofthemethylmethanoateproductgasesandthechemical

energyoftheethanoicacidproductgaseswouldbehigher.D. narrowerthantheMaxwell-Boltzmanndistributionofthemethylmethanoateproductgasesandthechemical

energyoftheethanoicacidproductgaseswouldbehigher.


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END OF SECTION ATURN OVER

Question 29Whichofthefollowingcombinationsofbondscanbebrokenduringthebreakdownofaproteinthatapersonhaseaten?A. covalentbondsinthesecondarystructureandhydrogenbondsintheprimarystructureB. covalentbondsinthetertiarystructureandhydrogenbondsinthesecondarystructureC. covalentbondsinthesecondarystructureandhydrogenbondsinthetertiarystructureD. covalentbondsinthequaternarystructureandhydrogenbondsintheprimarystructure

Question 30Considerthefollowinghalf-equation.

ClO2(g)+e− ⇌ClO2−(aq)

Itisalsoknownthat:• ClO2(g)willoxidiseHI(aq),butnotHCl(aq)• Fe3+(aq)willoxidiseHI(aq),butnotNaClO2(aq).

Basedonthisinformation,Fe2+(aq)canbeoxidisedbyA. Cl2(g)andI2(aq).B. Cl2(g),butnotClO2(g).C. ClO2(g)andCl2(g),butnotI2(aq).D. Cl2(g),ClO2(g)andI2(aq).


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SECTION B – Question 1–continued

Question 1 (9marks)Methanolisaveryusefulfuel.Itcanbemanufacturedfrombiogas.Themainreactioninmethanolproductionfrombiogasisrepresentedbythefollowingequation.

CO(g)+2H2(g)⇌ CH3OH(g) ΔH<0

Thisreaction requirestheuseofacatalysttomaximisetheyieldofmethanolproducedinoptimumconditions.Theenergyprofilediagrambelowrepresentstheuncatalysedreaction.

CO + 2H2

CH3OH

enthalpychange

(kJ mol–1)

reaction progress

a. Ontheenergyprofilediagramabove,sketchhowthecatalystwouldalterthereactionpathway. 1mark

SECTION B

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


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SECTION B – continuedTURN OVER

b. i. Howdoesthereactiontemperatureaffecttheyieldofmethanolfrombiogas?Inyouranswer,refertoLeChatelier’sprinciple. 2marks

ii. Howdoesthereactionpressureaffecttheyieldofmethanolfrombiogas?Inyouranswer,refertoLeChatelier’sprinciple. 2marks

c. Writetheexpressionfortheequilibriumconstant,Kc,forthisreaction. 1mark

d. 0.760molofcarbonmonoxide,CO,and0.525molofhydrogen,H2,wereallowedtoreachequilibriumina500mLcontainer.Atequilibriumthemixturecontained0.122molofmethanol.

Calculatetheequilibriumconstant,Kc. 3marks


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Question 2 (8marks)Theelectrolysisofcarbondioxidegas,CO2,inwaterisonewayofmakingethanol,C2H5OH.ThediagrambelowshowsaCO2–H2Oelectrolysiscell.Theelectrolyteusedintheelectrolysiscellissodiumbicarbonatesolution,NaHCO3(aq).

CO2(g)

power+ –

Cu–Zn electrodegraphite electrode

NaHCO3(aq)

Thefollowinghalf-cellreactionsoccurintheCO2–H2Oelectrolysiscell.

O2(g)+2H2O(l)+4e− ⇌4OH−(aq) E0=+0.40V2CO2(g)+9H2O(l)+12e− ⇌C2H5OH(l)+12OH−(aq) E0=−0.33V

a. IdentifytheCu–Znelectrodeaseithertheanodeorthecathodeintheboxprovidedinthediagramabove. 1mark

b. Determinetheappliedvoltagerequiredfortheelectrolysiscelltooperate. 1mark

c. Writethebalancedequationfortheoverallelectrolysisreaction. 1mark


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d. Identifytheoxidisingagentintheelectrolysisreaction.Giveyourreasoningusingoxidationnumbers. 2marks

e. Acurrentof2.70AispassedthroughtheCO2–H2Oelectrolysiscell.Thecellhasanefficiency of58%.

Calculatethetimetaken,inminutes,forthiscelltoconsume6.05×10−3molofCO2(g). 3marks


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Question 3 (7marks)Belowisareactionpathwaybeginningwithhex-3-ene.

O O

Compound L

hex-3-ene

HBr(aq)

hexan-3-ol

H+(aq)/MnO4

– (aq)

Reagent(s)

H2SO4(l)

Compound M

Compound J

Compound K

a. WritetheIUPACnameofCompoundJintheboxprovided. 1mark

b. Statethereagent(s)requiredtoconverthex-3-enetohexan-3-olintheboxprovided. 1mark


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c. Drawthestructuralformulaforatertiaryalcoholthatisanisomerofhexan-3-ol. 1mark

d. Hexan-3-olisreactedwithCompoundMunderacidicconditionstoproduceCompoundL.

Drawthesemi-structuralformulaforCompoundMintheboxprovidedonpage20. 1mark

e. i. Drawthesemi-structuralformulaforCompoundKintheboxprovidedonpage20. 1mark

ii. Nametheclassoforganiccompound(homologousseries)towhichCompoundKbelongs. 1mark

f. WhattypeofreactionproducesCompoundKfromhexan-3-ol? 1mark


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Question 4 (7marks)Researchscientistsaredevelopingarechargeablelithium–carbondioxide,Li–CO2,battery.TherechargeableLi–CO2batteryismadeoflithiummetal,carbonintheformofgraphite(coatedwithacatalyst)andanon-aqueouselectrolytethatabsorbsCO2.AdiagramoftherechargeableLi–CO2cellisshownbelow.OneLi–CO2cellgenerates4.5V.

CO2(g) CO2(g)

Li+

Li+

CO32– CO3

2–

lithium graphite

catalyst coating

non-aqueouselectrolyte

membrane

load

a. WhentheLi–CO2cellgenerateselectricity,thetwohalf-cellreactionsare

4Li++3CO2+4e− →2Li2CO3+CLi→Li++e−

Writetheequationfortheoverallrechargereaction. 1mark


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b. Duringdischarge,lithiumcarbonate,Li2CO3,depositsbreakawayfromtheelectrode.

Describehowthismightaffecttheperformanceofthebattery. 2marks

c. ExplainwhyitisunsafetouseanaqueouselectrolyteinthedesignoftheLi–CO2battery.Includeappropriateequationsinyouranswer. 3marks

d. CouldtheLi–CO2batterybeusedtoreducetheamountofCO2(g)intheatmosphere?Giveyourreasoning. 1mark


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Question 5 (9marks)Bananasprovideessentialvitaminsandminerals,suchasvitaminB6andvitaminC,alongwithdietaryfibreandenergy.Duringtheripeningprocess,thebananachangesinappearance,textureandtaste.Aripebananacontainsahighamountofglucose,whereasanunripebananacontainsupto80%starch.

a. Writeabalancedequationforcellularrespiration. 1mark

b. Thestructureofadisaccharidefoundinaripebananaisshownbelow.

CH2OH

CH2OH

CH2OHO

HOOH

OH OH

OH

O

O

i. Onthestructureabove,circleandnamethelinkthatjoinsthetwosugarunitsthatmakeupthedisaccharide. 1mark

ii. Namethetwosugarunitsthatmakeupthisdisaccharide. 1mark

iii. Bananaskinsareprimarilycomposedofcellulose.

Suggestwhycellulosecannotbeusedasasourceofenergyinthehumanbody. 1mark


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c. Thetablebelowshowstheamountofeachnutrientin100gofbanana.

Nutrient Per 100 g

protein 1.1g

carbohydrates 22.8g

fat 0.3g

dietaryfibre 2.6g

Anathleteuses300kJofenergyforafive-minuterun.Atypicalripebananahasanaveragemassof116gafteritispeeled.

Howmanytypicalripebananas,correcttotwodecimalplaces,wouldtheathleteneedtoconsumetoreplacetheenergyusedduringtherun?Showyourworking. 3marks

d. Duringtheripeningprocess,theenzymeamylasebreaksdownstarchmoleculesintodisaccharidesandmonosaccharides.

i. Whatnameisgiventothistypeofreaction? 1mark

ii. Theaminoacidlysineispresentintheprimarysequenceofamylase.

Drawthestructuralformulafortheaminoacidlysineinalow-pHsolution. 1mark


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SECTION B – continued

Question 6 (8marks)Methanegas,CH4,canbecapturedfromthebreakdownofwasteinlandfills.CH4isalsoaprimarycomponentofnaturalgas.CH4canbeusedtoproduceenergythroughcombustion.

a. WritetheequationfortheincompletecombustionofCH4toproducecarbonmonoxide,CO. 1mark

b. If20.0gofCH4iskeptina5.0Lsealedcontainerat25°C,whatwouldbethepressureinthecontainer? 2marks

c. ABunsenburnerisusedtoheatabeakercontaining350.0gofwater.Completecombustionof0.485gofCH4raisesthetemperatureofthewaterfrom20°Cto32.3°C.

CalculatethepercentageoftheBunsenburner’senergythatislosttotheenvironment. 3marks

d. ComparetheenvironmentalimpactofCH4obtainedfromlandfilltotheenvironmentalimpactofCH4 obtainedfromnaturalgas. 2marks


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SECTION B – Question 7–continuedTURN OVER

Question 7 (15marks)Insidetheshellofaneggiseggwhitethatencircleseggyolk.ThenutritioninformationforeggyolkandeggwhiteisgiveninTable1.

Table 1

Nutrient Per 100 g of egg yolk Per 100 g of egg white

energy 1437kJ 184kJ

fat 27.0g traceamounts

carbohydrate 0.0g 0.0g

protein 16.4g 10.8g

a. Poachinganegginvolvescrackinganeggandcarefullyplacingthecontentsinapanofhotwater.Thisallowstheeggwhitetosolidifyaroundtheeggyolk.

Usingyourknowledgeofchemistry,explainwhyvinegarissometimesaddedtothewatertoproduceapoachedeggwitharunnyyolk. 3marks


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b. ThecompositionoffattyacidsfoundinaneggyolksampleisgiveninTable2.Themeltingpointsforthefirstthreefattyacidsareprovided.

Table 2

Fatty acid Percentage (%) Melting point (°C)

palmitic 25.9 63

stearic 9.1 69

palmitoleic 3.4 0

oleic 40.9

linoleic 16.3

linolenic 2.9

arachidonic 1.5

i. Thecompositionoffattyacidsinaneggyolkwasdeterminedbyreactingthefattyacidswithmethanoltoproducemethylestersandthenanalysingthemethylestersusingchromatography.

Explain,usingtheprinciplesofchromatography,howeachfattyacidintheeggyolksamplecanbeidentifiedandthepercentagedetermined. 3marks


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ii. IdentifythefattyacidinTable2thatwouldhavethelowestflashpoint.Explainyouranswerintermsofboththe:• meltingpointtrendsshowninTable2• structureandbondingofthefattyacids. 4marks

c. i. Givethemolecularformulaandthemolarmassofthetriglycerideformedfromthreepalmitoleicacidmolecules. 2marks

ii. Calculatethemassofiodine,I2,ingrams,thatreactsinanadditionreactionwith100.0gofthetriglycerideformedfromthreepalmitoleicacidmolecules. 3marks


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Question 8 (7marks)AnunknownorganiccompoundhasamolecularformulaofC4H8O.Thecompoundisnon-cyclicandcontainsadouble bond.Theinfra-red(IR)spectrumofthemoleculeisshownbelow.

100

50

04000 3000 2000 1500

wave number (cm–1)1000 500

transmittance(%)


a. Whatdoestheregion3100–4000cm−1indicateaboutthebondsinC4H8O?Giveyourreasoning. 2marks


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b. The13CNMRspectrumoftheunknowncompoundhasfourdistinctpeaks.

Drawtwopossiblestructuralformulasoftheunknowncompoundusingtheinformationprovided. 2marks


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c. Thehigh-resolution1HNMRspectrumoftheunknowncompoundhasthreesinglepeaks,asshownbelow.

11 10 9 8 7 6ppm

5 4 3 2 1 0


Chemical shift (ppm) Relative peak area

1.82 3

3.53 3

3.85 2


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Refertothe1HNMRspectrumandthetableofspectruminformationprovidedonpage32.

Identifythreepiecesofinformationabouttheunknowncompoundandindicatehoweachwouldassistindeterminingitsstructure. 3marks

1.

2.

3.


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Question 9 (13marks)Astudentdecidedtoinvestigatetheeffectoftemperatureontherateofthefollowingreaction.

2HCl(aq)+CaCO3(s)→CaCl2(aq)+H2O(l)+CO2(g)

Partofthestudent’sexperimentalreportisprovidedbelow.

Effect of temperature on the rate of production of carbon dioxide gas

AimTofindouthowtemperatureaffectstherateofproductionofcarbondioxidegas,CO2,whenasolutionofhydrochloricacid,HCl,isaddedtochipsofcalciumcarbonate,CaCO3

Method1. Put0.6gofCaCO3chipsintoaconicalflask.2. Putareagentbottlecontaining2MHClintoawaterbathat5°C.3. WhenthetemperatureoftheHClsolutionhasstabilisedat5°C,useapipettetoput10.0mLoftheHCl

solutionintotheconicalflaskcontainingtheCaCO3chips.4. Putaballoonovertheconicalflaskandbegintiming.5. Whenthetopoftheballoonhasinflatedsothatitis10cmovertheconicalflask,stoptimingandrecordthe

time.6. Repeatsteps1–5usingtemperaturesof15°C,25°C,35°Cand45°C.

ResultsThefollowinggraphgivestheexperimentalresults.

Graph of experimental results

0 20 40time (s)

60 80 100

50

40

30

20

10

0

temperature(°C)


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a. Whatdoesthestudentneedtodotoensurethattheycomplywithallapplicablesafetyguidelinesduringtheinvestigation? 2marks

b. Whatistheindependentvariable? 1mark

c. Whatisthedependentvariableandhowisitmeasured? 2marks

d. i. Predicttherelationshipbetweentheindependentvariableandthedependentvariable.Explainyourprediction. 3marks

ii. Isthegraphofthestudent’sresultsconsistentwithyourprediction?Giveyourreasoning. 1mark


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SECTION B–continued

e. Identifytwowaysinwhichthegraphcouldhavebeenpresenteddifferentlytobetterillustratetherelationshipbetweentheindependentvariableandthedependentvariable. 2marks

f. Identifytwochangesthatcouldbemadetotheexperimentalmethodtoimprovetheprecisionoftheresultsiftheexperimentwasrepeated.Foreachchange,explainhowitwouldimproveprecision. 2marks


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CONTINUES OVER PAGE


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Question 10 (7marks)

Analyticalchemistrydealswithmethodsfordeterminingthechemicalcompositionofsamplesofmatter.Aqualitativemethodyieldsinformationabouttheidentityofatomicormolecularspeciesorthefunctionalgroupsinthesample…Analyticalmethodsareoftenclassifiedasbeingeitherclassicalorinstrumental.

Source:DASkoog,FJHollerandSRCrouch,Principles of Instrumental Analysis, 6thedition,ThomsonBrooks/Cole,Belmont(CA),2007,p.1

Classicalmethodsincludequalitativeanalysis,suchastreatingacompoundwithreagentstoobserveanyreaction,andquantitativemethods,suchasvolumetricanalysis,wheretheamountofacompoundisdeterminedbyitsreactionwithastandardreagent.Instrumentalmethodsincludeavarietyofspectroscopy,suchasIRspectroscopyandNMRspectroscopy.

a. Explainhowtheclassicalmethodsofanalyticalchemistrycanbeusedtodetermineinformationaboutalcohols.Inyouranswer,referto:• qualitativeanalysisandhowitcanbeusedtodeterminewhetheracompoundisanalcoholand,ifit

is,thetypeofalcohol• quantitativeanalysis. 3marks


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b. C3H6Ocanexistasaketoneorasaprimaryalcohol.

ExplainhowtheprinciplesofIRspectroscopyand1HNMRspectroscopyleadtodifferentspectrafortheketoneandprimaryalcoholisomersofC3H6O,whichcanthenbeusedtodifferentiatebetweenthetwomolecules. 4marks

END OF QUESTION AND ANSWER BOOK

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 2020

Victorian Certificate of Education 2020

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

( )− =

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

HO

β-fructose

OH

OH

OCH2OH

CH2OH

α-glucose

OH

OHHO

O

OH

CH2OH

α-lactoseOH

OH

HO O OCH2OH

OH

OHOH

OCH2OH


TURN OVER

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

OH

OH

n

cellulose

OH

OH

O

O

O

O

CH2OH

CH2OH


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.Heatofcombustionmaybedefinedastheheatenergyreleasedwhenaspecifiedamountofasubstanceburnscompletelyinoxygenandis,therefore,reportedasapositivevalue,indicating a magnitude. Enthalpy of combustion, ∆H, for the substances in this table would be reported as negativevalues,indicatingtheexothermicnatureofthecombustionreaction.

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 fuelsBlendedfuelsaremixturesofcompoundswithdifferentmixtureratiosand,hence,determinationofagenericmolar 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

2020 chemistry written examination

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