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ACHIEVEMENI
RECOGNISING
OXFORDCAMBRIDGEAND RSA EXAMINATIONS
AdvancedSubsidiaryGCE
2813/01
CHEMISTRY
HowFar,HowFast?
Wednesday
I JUNE 2005
45 minutes
Morning
Candidatesanswer on the questionpaper.
Additionalmaterials:
Data Sheet for Chemistry
Scientificcalculator
CandidateName
TIME
45 minutes
INSTRUCTIONS
TO CANDIDATES
Writeyournamein the spaceabove.
WriteyourCentrenumberand Candidatenumberin the boxesabove.
Answerall the questions.
Writeyouranswers,in the spacesprovidedon the questionpaper.
Readeachquestioncarefullyand makesureyou knowwhatyou haveto do beforestartingyour
answer.
FORCANDIDATES
INFORMATION
o
o
o
o
The numberof marksis givenin brackets[ ] at the endof eachquestionor partquestion.
Youmayusea scientificcalculator.
Youmay use the Data Sheeffor Chemistry.
FOR EXAMINER'SUSE
Youare advisedto showall the stepsin any calculations.
Qu.
Max.
1
10
2
15
3
11
4
9
TOTAL
45
Mark
This question paperconsists of 8 printed pages.
sP (NF/SLM)
573716/3
@ocR 2005 INlOOl3/.zsl
RegisteredCharity Number: 1066969
[Turn over
Fw
Examinefs
Use
2
Answerall the questions.
1
of
Thisquestionis abouthydrazine,
NrH4,and ammonia,NHr.Theseare bothcompounds
nitrogenand hydrogen.
(a) Hydrazinecan be oxidisedand used as a rocketfuel. The equationfor one possible
reactiontakingplaceis shownbelow.
H
\
/
H
H
N-N
H
/
+
\
Q:Q
+
+
N-N
2
H
Some averagebond enthalpiesare given below.
bond
bond enthalpy/ kJ mol-l
N_N
+163
N=N
+945
N_H
+390
o:o
+497
o-H
+463
Table1.1
(i) Use thesedatato calculatethe enthalpychangefor the reactionof hydrazinewith
oxygen,as shown.
answer
kJ mol-l t4l
(ii) Calculatethe enthalpychangefor one gramof hydrazine
in this reaction.
answer
2813/01Jun05
........
kJ t1l
3
(b) Ammoniareactswith oxygenin a very similarway to that shownfor hydrazine.The
the same as that for one
enthalpychangefor one gramof ammoniais approximately
gramof hydrazine.
For
Examiner's
Use
is usedas a rocketfuelandammonia
UsingTable1.1,suggesta reasonwhyhydrazine
is not.
.t1l
(c) Ammoniareactswithsulphuricacid,as shownin the equationbelow.
2NHs(g) + nrSoo(ao) -+
(NHr2So4(aq)
(i) Completethe statementbelow to describehow ammoniais behavingin this
reaction.
Ammoniais behavingas a
because
I2l
(ii) Stateone importantusefor the compound(NH/rSOo.
. . . . . tl1
(iii) Apart from the manufactureof (NH/2SO4,state one other large-scaleuse of
ammonia.
.t1l
[Total:10]
281UOl JunOS
[Turn over
For
Examinefs
Use
4
2
withequilibria
Thisquestionis concerned
thatexistbetweenoxidesof nitrogen.
principle.
(a) Statele Chatelier's
..t21
(b) Nitrogendioxide,NOr, is a browngas whilstdinitrogentetroxide,NrO4,is a colourless
gas.The followingequilibrium
betweenthesetwo gaseswasset up.
2NO2(g) <=a N2O4(g)
L,H = -58 kJmol-1
Describe,and explain,whatyouwouldsee afterthe followingchangeshavebeenmade
again.
andthe systemallowedto reachequilibrium
(i) The temperature
is increased.
.t3l
(ii) The pressureis increased.
281U01 Jun05
5
(c) NOeis an atmospheric
pollutantthat reactswithwateraccordingto the equationbelow.
2NO2(g)+ H2O(l) -+
For
Examiner's
Use
nruO.(aC)+ HruOr(aC) equation2.1
(i) Useoxidationnumbersof nitrogento explainwhy equation2.1 represents
a redox
reaction.
..t21
(ii) Statea likelysourceof NO, as an atmospheric
pollutant.
. . tl1
(d) The reactionof NO, with water,in equation2.1, occurswhen rain falls throughair
containing
NOz.
BothHNO3and HNO2arcacids.
Limestonecontainscalciumcarbonate,
CaCO..
(i) Whichion is responsible
for the acidproperties
of HNO.and HNO2?
t1l
(ii) Writethe ionic equationfor the reactionbetweencalciumcarbonateand HNO3.
.......t21
(iii) Norwichcathedralis builtfrom limestone.What will happento Norwichcathedral
overa periodof yearsif significant
amountsof NO, are presentin the atmosphere
aroundNorwich?
[Total:15]
281U01 JunOS
[Turn over
6
In an experimentto determinethe standardenthalpychangeof combustionof propan-1-ol,
a studentusedthe apparatusshownbelow.
CaHzOH,
Fw
Exaninefs
Use
propan-1-ol
(a) Definethe term enthalpychangeof combustion.
..t21
(b) Write the equationfor the standardenthalpychangeof combustionof propan-1-ol,
caHToH.
l2l
For
Exaninefs
Us
7
(c) The studentmeasured50.0cm3of waterinto the beakerand lit the burner.Whenthe
temperature
of the waterhad goneup by 12.8"C,he foundthat0.1009of propan-1-ol
hadbeenburnt.
(i) Calculatethe energy,in kJ, producedby burning0.1009 of propan-1-ol.
The
specificheatcapacityof wateris 4.18J g-t 6-t.
ener$l =
kJ l2l
(ii) Calculatethe numberof moles of propan-1-olin 0.100 g.
numberof moles= ................
l2I
(iii) Calculate
in kJmol-1,of propan-1-ol.
the enthalpychangeof combustion,
enthalpy
change
......kJmol-l t1l
(d) The studentlookedin a text book and found that the actualvalue for the standard
enthalpy change of combustionof propan-1-olwas more exothermicthan the
experimental
value.
Suggesttwo reasonsfor the differencebetweenthis valueand the one he obtained
experimentally.
1
2
.l2l
[Total:1 1 1
281V01 JunOS
[Turn over
For
Examinefs
Use
8
4
(a) What is a catalyst?
..t21
catalyst.
(b) Explainthe termsheterogeneouscatalystandhomogeneous
you should
In yourexplanation
.
includean exampleof a reactionfor each type of catalyst
.
includean equationfor one of yourreactions
.
describehowa heterogeneouscatalystworks.
17l
\
[Total:9]
PAPER
ENDOF QUESTION
any,we apologise.
overlooked
OCRhasmadeeveryeffortto tracethe copyrightholdersol itemsusedin thisQuestionpaper,butif we haveinadvertently
281U01 Jun05