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At the end of the examination, fasten all your work securely together.
The number of marks is given in brackets [ ] at the end of each question or part question.
CHEMISTRY 0620/31
Paper 3 Theory (Core) May/June 2019
1 hour 15 minutes
Candidates answer on the Question Paper.
No Additional Materials are required.
Cambridge Assessment International Education
Cambridge International General Certificate of Secondary Education
This document consists of 18 printed pages and 2 blank pages.
[Turn overIB19 06_0620_31/2RP
© UCLES 2019
*7118832773*
This syllabus is regulated for use in England, Wales and Northern Ireland as a Cambridge International Level 1/Level 2 Certificate.
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1 Thediagramsshowpartofthestructuresoffivesubstances,A,B,C,DandE.
Li+ Cl – Li+ Cl –
Cl – Li+ Li+Cl –
Li+ Cl – Li+ Cl –
Cl – Li+ Li+Cl –
Cu Cu Cu Cu
Cu Cu Cu Cu
Cu Cu Cu Cu
Cu Cu Cu Cu
He
HeHe
He
He
He
A B
D E
C
N N
NN
N
NNN
NN
(a) Answerthefollowingquestionsaboutthesestructures. Eachstructuremaybeusedonce,morethanonceornotatall.
(i) Which twoofthesestructures,A,B,C,D or E,arecovalentlybonded?
..................................................................and ................................................................... [2]
(ii) Which oneofthesestructures,A,B,C,D or E,isadiatomicmolecule?
....................................................................................................................................... [1]
(iii) Which oneofthesestructures,A,B,C,D or E,isacompound?
....................................................................................................................................... [1]
(iv) Which oneofthesestructures,A,B,C,D or E,isverysolubleinwater?
....................................................................................................................................... [1]
(v) Which oneofthesestructures,A,B,C,D or E,isusedincuttingtools?
....................................................................................................................................... [1]
(vi) Which oneofthesestructures,A,B,C,D or E,isusedinelectricalwiring?
....................................................................................................................................... [1]
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(b) SubstanceBisanelement.
Whatismeantbythetermelement?
....................................................................................................................................................
.............................................................................................................................................. [1]
[Total:8]
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2 Thisquestionisaboutironandironcompounds.
(a) Namethemainoreofiron.
.............................................................................................................................................. [1]
(b) Inablastfurnaceusedfortheextractionofiron,carbonreactswithoxygenfromtheairtoformcarbonmonoxide.
Completethechemicalequationforthisreaction.
....C + ..... 2CO
[2]
(c) Inthehotterpartsofthefurnace,carbonreactswiththeiron(III)oxidepresentintheironore.
3C + Fe2O3 3CO + 2Fe
Howdoesthisequationshowthatcarbonisoxidised?
....................................................................................................................................................
.............................................................................................................................................. [1]
(d) Limestoneisaddedtotheblastfurnace.Thelimestoneisconvertedintocalciumoxideandcarbondioxide.Thereactionisendothermic.
heatCaCO3 CaO + CO2
(i) Whattypeofchemicalreactionisthis?
....................................................................................................................................... [1]
(ii) Whattypeofoxideiscalciumoxide? Giveareasonforyouranswer.
.............................................................................................................................................
....................................................................................................................................... [2]
(e) Ironisametal.
Givethreephysicalpropertiesthatarecharacteristicofmetals.
1 .................................................................................................................................................
2 .................................................................................................................................................
3 .................................................................................................................................................
[3]
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(f) Thestructureofacompoundofironisshown.
CO
CO
OC COOC
COOC
COOC FeFe
Deduce themolecular formula of this compound to show the number of iron, carbon andoxygenatoms.
.............................................................................................................................................. [1]
[Total:11]
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3 (a) ThetableshowsthepercentagebymassoftheelementsonEarthandintheUniverse.
element percentagebymassonEarth
percentagebymassintheUniverse
helium 0.0 21.0
hydrogen 0.1 76.0
iron 35.0 1.0
magnesium 14.0 0.1
oxygen 29.0 0.8
silicon 14.0 0.1
sulfur 2.9 0.1
otherelements 0.9
total 100.0 100.0
Answerthesequestionsusingonlytheinformationinthetable.
(i) DeducethepercentagebymassofotherelementspresentonEarth.
.............................. % [1]
(ii) Whichnon-metallicelementispresentonEarthinthegreatestpercentagebymass?
....................................................................................................................................... [1]
(iii) GivetwomajordifferencesinthepercentagebymassoftheelementsonEarthandintheUniverse.
1 ..........................................................................................................................................
.............................................................................................................................................
2 ..........................................................................................................................................
.............................................................................................................................................
[2]
(b) Completethediagramtoshowtheelectronarrangementinanoxygenatom.
[1]
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(c) Helium,neonandargonarenoblegases.
(i) Explain,intermsoftheelectronicstructure,whyneonisunreactive.
.............................................................................................................................................
....................................................................................................................................... [1]
(ii) State oneuseofargon.
....................................................................................................................................... [1]
[Total:7]
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4 Thisquestionisaboutiodineandcompoundsofiodine.
(a) Usethekineticparticlemodeltodescribetheseparationbetweenthemoleculesandthetypeofmotionofthemoleculesin:
● solidiodine ..........................................................................................................................
....................................................................................................................................................
● iodinegas. ..........................................................................................................................
....................................................................................................................................................
[4]
(b) Thegraphshowshowthevolumeofiodinegaschangeswithpressure.Thetemperatureiskeptconstant.
volume of
iodine gas
pressure00
Describehowthevolumeofiodinegaschangeswithpressure.
....................................................................................................................................................
.............................................................................................................................................. [1]
(c) (i) Complete thewordequationtoshowthehalogenandhalidecompoundwhichreact toformtheproductsiodineandpotassiumbromide.
........................+
........................
........................
iodine +potassium
bromide
[2]
(ii) Explain,intermsofthereactivityofthehalogens,whyaqueousiodinedoesnot react with
aqueouspotassiumchloride.
.............................................................................................................................................
....................................................................................................................................... [1]
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(d) Iodinereactswithaqueoussodiumthiosulfate,Na2S2O3.
(i) Balancethechemicalequationforthisreaction.
.....Na2S2O3 + I2 Na2S4O6 + .....NaI
[2]
(ii) Theenergyleveldiagramforthisreactionisshown.
energy
reactants
products
progress of reaction
Explainhowthisdiagramshowsthatthereactionisexothermic.
.............................................................................................................................................
....................................................................................................................................... [1]
(e) Describeatestforiodideions.
test .............................................................................................................................................
observations .............................................................................................................................. [2]
(f) Moltensodiumiodideiselectrolysed.
Predicttheproductatthepositiveelectrode.
.............................................................................................................................................. [1]
[Total:14]
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5 Coalgasismadebyheatingcoalintheabsenceofair. Thelistshowsthemaingasespresentincoalgas.
carbon dioxide
carbon monoxide
ethene
hydrogen
methane
nitrogen
(a) (i) Which oneofthesegasesisanalkane?
....................................................................................................................................... [1]
(ii) Drawthestructureofamoleculeofethene.Showalloftheatomsandallofthebonds.
[1]
(iii) Describehowaqueousbrominecanbeusedtotellthedifferencebetweenmethaneandethene.
.............................................................................................................................................
.............................................................................................................................................
....................................................................................................................................... [2]
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(b) Ethenemoleculesreactwitheachothertoformpoly(ethene).
(i) Whatisthenamegiventothistypeofchemicalreaction?
....................................................................................................................................... [1]
(ii) Which oneofthefollowingwordsdescribestheethenemoleculesinthisreaction? Drawacirclearoundthecorrectanswer.
elements mixtures monomers polymers
[1]
(iii) Poly(ethene)isanon-biodegradableplastic.
Whatismeantbythetermnon-biodegradable?
.............................................................................................................................................
....................................................................................................................................... [1]
(iv) Describeonepollutionproblemcausedbynon-biodegradableplastics.
.............................................................................................................................................
....................................................................................................................................... [1]
(c) Ethanolcanbemadefrometheneandoneotherreactant.
● Nametheotherreactant.
....................................................................................................................................................
● Statetheconditionsneededtomakeethanolfromethene.
....................................................................................................................................................
....................................................................................................................................................
[3]
[Total:11]
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6 Thisquestionisaboutcopperandcoppercompounds.
(a) Describehowyoucouldprepareapuresampleofcrystalsofhydratedcopper(II)sulfateusingdilutesulfuricacidandanexcessofcopper(II)oxide.
....................................................................................................................................................
....................................................................................................................................................
....................................................................................................................................................
....................................................................................................................................................
.............................................................................................................................................. [3]
(b) Anhydrouscopper(II)sulfateisusedtotestforwater.
CuSO4 + 5H2O CuSO4.5H2O
anhydrous hydrated copper(II)sulfate copper(II)sulfate
(i) Whatismeantbythesymbol ?
....................................................................................................................................... [1]
(ii) Howcanhydratedcopper(II)sulfatebechangedintoanhydrouscopper(II)sulfate?
....................................................................................................................................... [1]
(c) Complete the table to calculate the relative formulamass of anhydrous copper(II) sulfate,CuSO4.
UseyourPeriodicTabletohelpyou.
type of atomnumberof atoms
relativeatomic mass
copper 1 64 1 × 64 = 64
sulfur
oxygen
relativeformulamass=............................... [2]
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(d) Completethetabletoshowthenumberofelectrons,protonsandneutronsinthesulfuratomandcopperionshown.
numberofelectrons
numberofneutrons
numberofprotons
34S16
63Cu2+29
29
[4]
(e) Alloysofcopperareusedtomakecoins.
(i) Whatismeantbythetermalloy?
.............................................................................................................................................
....................................................................................................................................... [1]
(ii) Suggestwhyanalloyofcopperisusedtomakecoinsinsteadofusingpurecopper.
....................................................................................................................................... [1]
[Total:13]
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7 Astudentinvestigatestherateofreactionofsmallpiecesofcalciumcarbonatewithanexcessofhydrochloricacidofconcentration1mol/dm3.
CaCO3(s)+2HCl(aq) CaCl 2(aq)+CO2(g)+H2O(l)
(a) Namethesaltformedwhencalciumcarbonatereactswithhydrochloricacid.
.............................................................................................................................................. [1]
(b) Thegraphshowshowthemassofthereactionmixturechangeswithtime.
200.0
199.8
199.6
199.4
199.2
199.0
198.80 20 40 60
time / s
80 100 120 140
mass of
reaction
mixture
/ g
(i) Statewhythereactionmixturedecreasesinmass.
....................................................................................................................................... [1]
(ii) Calculatethelossinmassduringthefirst40secondsoftheexperiment.
.............................. g [1]
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(iii) Theexperimentisrepeatedusinghydrochloricacidofconcentration2mol/dm3.
Allotherconditionsarekeptthesame.
Draw a line on the grid for the experiment using hydrochloric acid of concentration2mol/dm3. [2]
(iv) In the experiment,when 2.00g of calcium carbonate is used, the loss inmass of thereactionmixtureis0.88g.
Allotherconditionsarekeptthesame.
Calculatethelossinmasswhen0.50gofcalciumcarbonateisused.
lossinmass=..............................g[1]
(v) The experiment is repeated using the same mass of different sized pieces ofcalciumcarbonate.
Allotherconditionsarekeptthesame.
Thesizesofthepiecesofcalciumcarbonateare:
● powder ● smallpieces ● largepieces.
Complete the table bywriting the sizesof thepiecesof calciumcarbonate in the firstcolumn.
sizeofpiecesofcalciumcarbonate
initialrateoflossinmassing/s
0.005
0.030
0.100
[1]
[Total:7]
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8 (a) Sulfurdioxideisapollutantintheair.
(i) State onesourceofsulfurdioxideintheair.
....................................................................................................................................... [1]
(ii) Sulfurdioxideisoxidisedtosulfurtrioxideintheair. Oxidesofnitrogenactascatalystsforthisreaction.
Whatismeantbythetermcatalyst?
.............................................................................................................................................
....................................................................................................................................... [1]
(iii) Sulfurtrioxidedissolvesinrainwatertoformacidrain.
Which oneofthefollowingpHvaluescouldbethepHofacidrain? Drawacirclearoundthecorrectanswer.
pH 4 pH 7 pH 9 pH 13
[1]
(iv) State oneadverseeffectofacidrainonbuildings.
....................................................................................................................................... [1]
(b) Sulfurdioxidemeltsat–73°Candboilsat–10°C.
Whatisthephysicalstateofsulfurdioxideat–20°C? Explainyouranswer.
....................................................................................................................................................
.............................................................................................................................................. [2]
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(c) Excesssulfuricacidreactswithammoniatomakeasaltwhichcanbeusedasafertiliser.
Statethenameofthesaltformedwhenexcesssulfuricacidreactswithammonia.
.............................................................................................................................................. [1]
(d) Thetableshowssomeobservationsaboutthereactivityoffourmetalswithdilutesulfuricacid.
metal reactionwithsulfuricacid
iron aslowstreamofbubblesisseen
magnesium arapidstreamofbubblesisseen
nickel afewbubblesslowlyform
tungsten nobubblesareseen
Usetheinformationinthetabletoputthefourmetalsinorderoftheirreactivity. Puttheleastreactivemetalfirst.
least reactive most reactive
[2]
[Total:9]
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20
0620/31/M/J/19© UCLES 2019
Gro
up
Th
e P
eri
od
ic T
ab
le o
f E
lem
en
ts
1 Hh
yd
rog
en
1
2
He
he
lium
4
III
III
IVV
VI
VII
VII
I
3 Li
lith
ium
7
4 Be
be
rylli
um
9
ato
mic
nu
mb
er
ato
mic
sym
bo
l
Ke
y
na
me
rela
tive
ato
mic
ma
ss
11
Na
so
diu
m
23
12
Mg
ma
gn
esiu
m
24
19 K
po
tassiu
m
39
20
Ca
ca
lciu
m
40
37
Rb
rub
idiu
m
85
38
Sr
str
on
tiu
m
88
55
Cs
ca
esiu
m
13
3
56
Ba
ba
riu
m
13
7
87
Fr
fra
nciu
m
–
88
Ra
rad
ium
–
5 Bb
oro
n
11
13
Al
alu
min
ium
27
31
Ga
gallium
70
49
In
indium
115
81 Tl
thallium
204
6 Ccarbon
12
14 Si
silicon
28
32
Ge
germanium
73
50
Sntin
119
82
Pb
lead
207
22 Ti
titanium
48
40
Zr
zirconium
91
72
Hf
hafnium
178
104
Rf
rutherfordium
–
23 V
vanadium
51
41
Nb
niobium
93
73
Ta
tantalum
181
105
Db
dubnium
–
24
Cr
chromium
52
42
Mo
molybdenum
96
74
Wtungsten
184
106
Sg
seaborgium
–
25
Mn
manganese
55
43
Tc
technetium
– 75
Re
rhenium
186
107
Bh
bohrium
–
26
Fe
iron
56
44
Ru
ruthenium
101
76
Os
osmium
190
108
Hs
hassium
–
27
Co
cobalt
59
45
Rh
rhodium
103
77
Ir
iridium
192
109
Mt
meitnerium
–
28
Ni
nickel
59
46
Pd
palladium
106
78
Pt
platinum
195
110
Ds
darmstadtium
–
29
Cu
copper
64
47
Ag
silver
108
79
Au
gold
197
111
Rg
roentgenium
–
30
Zn
zinc
65
48
Cd
cadmium
112
80
Hg
mercury
201
112
Cn
copernicium
–
114
Fl
flerovium
–
116
Lv
livermorium
–
7 Nnitrogen
14
15 P
phosphorus
31
33
As
arsenic
75
51
Sb
antimony
122
83 Bi
bismuth
209
8 Ooxygen
16
16 S
sulfur
32
34
Se
selenium
79
52
Te
tellurium
128
84
Po
po
lon
ium
–
9 Fflu
orin
e
19
17
Cl
ch
lorin
e
35
.5
35
Br
bro
min
e
80
53 I
iod
ine
12
7
85
At
asta
tin
e
–
10
Ne
ne
on
20
18
Ar
arg
on
40
36
Kr
kry
pto
n
84
54
Xe
xe
no
n
13
1
86
Rn
rad
on
–
21
Sc
sca
nd
ium
45
39 Y
ytt
riu
m
89
57
–7
1
lan
tha
no
ids
89
–1
03
actin
oid
s
57
La
lan
tha
nu
m
13
9
89
Ac
lan
tha
no
ids
actin
oid
s
Th
e v
olu
me
of
on
e m
ole
of
an
y g
as is 2
4 d
m3 a
t ro
om
te
mp
era
ture
an
d p
ressu
re (
r.t.
p.)
.
actin
ium
–
58
Ce
ce
riu
m
140
90
Th
thorium
232
59
Pr
praseodymium
141
91
Pa
protactinium
231
60
Nd
neodymium
144
92 U
uranium
238
61
Pm
promethium
– 93
Np
neptunium
–
62
Sm
samarium
150
94
Pu
plutonium
–
63
Eu
europium
152
95
Am
americium
–
64
Gd
gadolinium
157
96
Cm
curium
–
65
Tb
terbium
159
97
Bk
berkelium
–
66
Dy
dysprosium
163
98
Cf
californium
–
67
Ho
holmium
165
99
Es
einsteinium
–
68
Er
erbium
167
100
Fm
fermium
–
69
Tm
thulium
169
101
Md
mendelevium
–
70
Yb
ytterbium
173
102
No
nobelium
–
71
Lu
lutetium
175
103
Lr
lawrencium
–