SlideShare uma empresa Scribd logo
1 de 12
Baixar para ler offline
UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
International General Certificate of Secondary Education

*4888728650*

CHEMISTRY

0620/32

Paper 3 (Extended)

October/November 2011
1 hour 15 minutes

Candidates answer on the Question Paper.
No Additional Materials are required.
READ THESE INSTRUCTIONS FIRST
Write your Centre number, candidate number and name on all the work you hand in.
Write in dark blue or black pen.
You may use a pencil for any diagrams, graphs or rough working.
Do not use staples, paper clips, highlighters, glue or correction fluid.
DO NOT WRITE IN ANY BARCODES.
Answer all questions.
A copy of the Periodic Table is printed on page 12.
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.

For Examiner’s Use
1
2
3
4
5
6
7
Total

This document consists of 12 printed pages.
IB11 11_0620_32/2RP
© UCLES 2011

[Turn over
2
1

For
Examiner’s
Use

Cobalt is an element in Period 4 of the Periodic Table.
(a) Use your copy of the Periodic Table to help you complete the table below.
particle

number of
protons

number of
neutrons

number of
electrons

Co
Co2+
[2]
(b)

60

Co is a cobalt isotope.

(i) Explain the term isotope.
....................................................................................................................................
....................................................................................................................................
.............................................................................................................................. [2]
(ii) Explain why two isotopes of the same element have identical chemical properties.
.............................................................................................................................. [1]
(iii) State one industrial use and one medical use of radioactive isotopes.
industrial use ....................................................................................................... [1]
medical use ......................................................................................................... [1]
[Total: 7]

© UCLES 2011

0620/32/O/N/11
3
2

For
Examiner’s
Use

Sulfur is needed for the production of sulfuric acid. Two of the major sources of sulfur are
● underground deposits of the element sulfur,
● sulfur compounds from natural gas and petroleum.
(a) Explain why sulfur and its compounds are removed from these fuels before they are
burned.
...........................................................................................................................................
..................................................................................................................................... [2]
(b) Sulfur dioxide is made by spraying molten sulfur into air. The sulfur ignites and sulfur
dioxide is formed.
(i) Suggest why molten sulfur is used in the form of a fine spray.
....................................................................................................................................
.............................................................................................................................. [2]
(ii) Explain why traces of sulfur dioxide act as a preservative in fruit juices.
.............................................................................................................................. [1]
(iii) State another use of sulfur dioxide.
.............................................................................................................................. [1]
(c) Describe how sulfur dioxide is changed into sulfur trioxide. Give the reaction conditions
and an equation.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
..................................................................................................................................... [4]
(d) Complete the following equations for the formation of sulfuric acid from sulfur trioxide.
SO3 + ............... → H2S2O7
H2S2O7 + ………. → ..........H2SO4

[2]
[Total: 12]

© UCLES 2011

0620/32/O/N/11

[Turn over
4
3

For
Examiner’s
Use

Antimony, Sb, is an element in Group V.
(a) The main ore of antimony is its sulfide. The extraction of antimony is similar to that of
zinc.
Describe how each of these changes in the extraction of antimony is carried out.
(i) antimony sulfide to antimony oxide
.............................................................................................................................. [1]
(ii) antimony oxide to antimony
.............................................................................................................................. [1]
(b) Antimony oxide is a white powder which is insoluble in water.
Describe how you would find out if it is a basic, an acidic or an amphoteric oxide.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
..................................................................................................................................... [4]
(c) When antimony chloride is added to water, a faint white precipitate forms and the mixture
slowly goes cloudy.
forward
SbCl 3(aq) + H2O(l)
colourless

2HCl (aq) + SbOCl (s)

backward

white

(i) Explain why after some time the appearance of the mixture remains unchanged.
....................................................................................................................................
.............................................................................................................................. [2]
(ii) When a few drops of concentrated hydrochloric acid are added to the mixture, it
changes to a colourless solution. Suggest an explanation.
....................................................................................................................................
.............................................................................................................................. [1]
(iii) Suggest how you could make the colourless solution go cloudy.
.............................................................................................................................. [1]
[Total: 10]

© UCLES 2011

0620/32/O/N/11
5
4

For
Examiner’s
Use

The structure of an element or compound determines its physical properties.
Scandium fluoride and silicon(IV) oxide have giant structures.
(a) Scandium fluoride is an ionic compound.
(i) The valency of scandium is three. Draw a diagram which shows the formula of the
compound, the charges on the ions and the arrangement of the valency electrons
around the negative ion.
Use x to represent an electron from a scandium atom.
Use o to represent an electron from a fluorine atom.

[3]
(ii) The melting point of scandium fluoride is 1552 °C. Explain why scandium fluoride
has a high melting point.
....................................................................................................................................
.............................................................................................................................. [1]
(b) Silicon(IV) oxide has a macromolecular structure.
(i) Describe the structure of silicon(IV) oxide. You may use a diagram.

[3]
(ii) How does the electrical conductivity of these two compounds differ?
....................................................................................................................................
.............................................................................................................................. [1]
(iii) Explain the difference in conductivity.
....................................................................................................................................
.............................................................................................................................. [2]
[Total: 10]
© UCLES 2011

0620/32/O/N/11

[Turn over
6
5

The alcohols form a homologous series. Two characteristics of a homologous series are
that the physical properties of the members vary in a predictable way and they have similar
chemical properties.
(a) Complete the table.
name

mass of one
mole / g

formula

boiling point
/ °C

methanol

CH3 – OH

32

64

ethanol

CH3 – CH2 – OH

46

78

propan-1-ol

CH3 – CH2 – CH2 – OH

60

98

butan-1-ol

CH3 – CH2 – CH2 – CH2 – OH

74

118

pentan-1-ol
hexan-1-ol

138
CH3 – CH2 – CH2 – CH2 – CH2 – CH2 – OH

102
[3]

(b) Give two other characteristics of a homologous series.
...........................................................................................................................................
..................................................................................................................................... [2]
(c) Draw a diagram showing the arrangement of the valency electrons in one molecule of
the covalent compound methanol.
Use x to represent an electron from a carbon atom.
Use o to represent an electron from an oxygen atom.
Use ● to represent an electron from a hydrogen atom.

[3]

© UCLES 2011

0620/32/O/N/11

For
Examiner’s
Use
7
(d) Alcohols can be oxidised to carboxylic acids by heating with acidic potassium
manganate(VII).

For
Examiner’s
Use

(i) Draw the structural formula of the carboxylic acid formed by the oxidation of
propan-1-ol. Show all the bonds.

[1]
(ii) Describe how ethanol could be oxidised to ethanoic acid by fermentation.
....................................................................................................................................
.............................................................................................................................. [2]
(e) Propan-1-ol and ethanoic acid react together to form an ester. Give its name and structural
formula.
name ........................................................................................................................... [1]
formula

[1]
[Total: 13]

© UCLES 2011

0620/32/O/N/11

[Turn over
8
6

Soluble salts can be made by the neutralisation of an acid by a base. Insoluble salts can be
made by precipitation.
(a) The following is a brief description of the preparation of the soluble salt,
nickel(II) chloride-6-water, from the insoluble base nickel(II) carbonate.
Nickel(II) carbonate is added in small amounts to hot dilute hydrochloric acid until it is
in excess. The mixture is filtered. The filtrate is partially evaporated and then allowed to
cool until crystals of nickel(II) chloride-6-water form.
(i) Why is it necessary to use excess carbonate?
....................................................................................................................................
.............................................................................................................................. [1]
(ii) Explain why it is necessary to filter.
.............................................................................................................................. [1]
(iii) Why partially evaporate rather than evaporate to dryness?
....................................................................................................................................
.............................................................................................................................. [1]
(iv) What additional steps are needed to obtain dry crystals?
....................................................................................................................................
.............................................................................................................................. [2]
(b) Potassium chloride can be made from hydrochloric acid and potassium carbonate.
(i) Why must a different experimental method be used for this preparation?
....................................................................................................................................
.............................................................................................................................. [1]
(ii) Give a description of the different method used for this salt preparation.
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
.............................................................................................................................. [4]

© UCLES 2011

0620/32/O/N/11

For
Examiner’s
Use
9
(c) Insoluble salts are made by precipitation. An equation for the preparation of barium
sulfate is given below.

For
Examiner’s
Use

BaCl 2(aq) + MgSO4(aq) → BaSO4(s) + MgCl 2(aq)
This reaction can be used to find x in the formula for hydrated magnesium sulfate
MgSO4.xH2O.
A known mass of hydrated magnesium sulfate, MgSO4.xH2O, was dissolved in water.
Excess aqueous barium chloride was added. The precipitate of barium sulfate was
filtered, washed and dried. Finally it was weighed.
Mass of hydrated magnesium sulfate = 1.476 g
Mass of barium sulfate formed = 1.398 g
The mass of one mole of BaSO4 = 233 g
The number of moles of BaSO4 formed = ...............

[1]

The number of moles of MgSO4.xH2O = ...............

[1]

The mass of one mole of MgSO4.xH2O = ............... g

[1]

The mass of one mole of MgSO4 = 120 g
The mass of xH2O in one mole of MgSO4.xH2O = ...............

[1]

x = ...............

[1]
[Total: 15]

© UCLES 2011

0620/32/O/N/11

[Turn over
10
7

Petrol is a mixture of hydrocarbons and additives. The combustion of petrol in car engines is
a major source of air pollution. This is reduced by catalytic converters.
(a) Petrol is obtained from the gasoline fraction, boiling point range 40 °C to 100 °C, from the
distillation of petroleum. Explain the term fraction.
...........................................................................................................................................
..................................................................................................................................... [2]
(b) In many countries, a lead compound of the type Pb(C2H5)n used to be added to petrol to
improve its combustion. After combustion, lead oxide was formed.

LEADED
98 OCTANE

(i) Octane is a constituent of petrol. Write the equation for the complete combustion of
octane.
C8H18 + ...............O2 → ............... + ...............

[2]

(ii) Dibromoethane was added to petrol to remove the lead oxide from inside the engine.
Lead bromide was formed which escaped into the environment through the exhaust.
Leaded petrol cannot be used with a catalytic converter. Give another reason why
leaded petrol is no longer used.
.............................................................................................................................. [1]
(iii) What does each of the following tell you about the structure of dibromoethane?
dibromo ......................................................................................................................
eth ..............................................................................................................................
ane ....................................................................................................................... [2]
(iv) What additional information is needed to draw the structural formula of
dibromoethane?
.............................................................................................................................. [1]

© UCLES 2011

0620/32/O/N/11

For
Examiner’s
Use
11
(c) An analysis of the compound, Pb(C2H5)n , showed that 0.026 moles of Pb was combined
with 0.104 moles of C2H5 groups.
What is the value of n? Show how you arrived at your answer.
...........................................................................................................................................
..................................................................................................................................... [2]
(d) Some of the pollutants emitted by vehicle exhausts are carbon monoxide, oxides of
nitrogen and unburnt hydrocarbons. Explain how the emission of these gases is reduced
by a catalytic converter.
...........................................................................................................................................
...........................................................................................................................................
..................................................................................................................................... [3]
[Total: 13]

© UCLES 2011

0620/32/O/N/11

For
Examiner’s
Use
© UCLES 2011

24

40

Sodium

Calcium

88

0620/32/O/N/11

89

Key

b

X

a

72

b = proton (atomic) number

X = atomic symbol

a = relative atomic mass

*58-71 Lanthanoid series
90-103 Actinoid series

88

Ac

Actinium

Ra

Radium

Fr

Francium

87

*

Hafnium

Lanthanum

57

Hf

La

40

Zirconium

Zr

91

Titanium

178

Yttrium

22

48

Ti

139

39

Y

89

Scandium

21

227

Caesium

56

Barium

Cs

45

Sc

226

55

137

Ba

133

Strontium

Rubidium

38

Rb

37

Sr

85

20

Potassium

19

Ca

39

Magnesium

Na

12

Mg

23

Beryllium

4

Lithium

K

11

3

9

Be

7

II

Li

I

51

93

Ta

181

Niobium

Nb

90

58

73

52

96

Mo

W

184

141

Pa

Thorium

55

Tc
186

Re

144

Nd

92

60

Uranium

U

238

Neodymium

75

Rhenium

43

Technetium

25

Manganese

Mn
29

30

65

8

9

VII

2

0

Ru

101

Iron

190

Pm

Osmium

Os

93

Np
Neptunium

61

Promethium

76

44

Ruthenium

26

56

Fe

192

Sm

150

Iridium

Ir

94

Pu
Plutonium

62

Samarium

77

45

Rhodium

Rh

103

Cobalt

Co

195

Eu

152

Platinum

Pt

95

Am
Americium

63

Europium

78

46

Palladium

Pd

106

Nickel

Ni

Gd

157

Gold

Au

197

Silver

96

64

Curium

Cm

Gadolinium

79

47

Ag

108

Copper

Cu

201

Bk

Terbium

Tb

159

Mercury

Hg

97

Berkelium

65

80

48

Cadmium

Cd

112

Zinc

Zn

11

70

Dy

162

Thallium

Tl

204

Indium

In

115

Gallium

Ga

98

Cf
Californium

66

Dysprosium

81

49

31

13

Aluminium

119

Es

Holmium

Ho

165

Lead

Pb

207

Tin

Sn

99

Einsteinium

67

82

50

32

Germanium

Ge

73

Silicon

Si

Al
14

28

Carbon

27

Boron

12

C

14

75

Sb

122

Arsenic

As

Bi

209

Fermium

Fm

Erbium

Er

167

Bismuth

100

68

83

51

Antimony

33

15

Phosphorus

P

31

Nitrogen

N

Se

79

Sulfur

S

32

Oxygen

Po

169

Md

Thulium

Tm

101

Mendelevium

69

84

Polonium

52

Tellurium

Te

128

Selenium

34

16

16

O

Yb

173

Astatine

At

Iodine

I

127

Bromine

Br

80

Chlorine

No
102

Nobelium

70

Ytterbium

85

53

35

17

Cl

35.5

Fluorine

F

19

Lr

Lutetium

Lu

175

Radon

Rn

Xenon

Xe

131

Krypton

Kr

84

Argon

Ar

40

Neon

103

Lawrencium

71

86

54

36

18

10

Ne

20

Helium

Hydrogen

B

4

28

64

7

VI

He

27

59

6

V

H

59

5

IV

The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).

91

Protactinium

Th

232

Praseodymium

Cerium

59

Pr

Ce

74

Tungsten

42

Molybdenum

24

Chromium

Cr

140

Tantalum

41

23

Vanadium

V

1

III
1

Group

DATA SHEET
The Periodic Table of the Elements

12

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every
reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included the
publisher will be pleased to make amends at the earliest possible opportunity.

University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of
Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

Mais conteúdo relacionado

Mais procurados

0580_s14_qp_43
0580_s14_qp_430580_s14_qp_43
0580_s14_qp_43King Ali
 
0625_s14_qp_32
0625_s14_qp_320625_s14_qp_32
0625_s14_qp_32King Ali
 
Cambridge Lower Secondary Checkpoint Past Paper P2 october-2018-science
Cambridge  Lower Secondary Checkpoint Past Paper P2 october-2018-scienceCambridge  Lower Secondary Checkpoint Past Paper P2 october-2018-science
Cambridge Lower Secondary Checkpoint Past Paper P2 october-2018-scienceSmart Exam Resources
 
0625 w08 qp_03
0625 w08 qp_030625 w08 qp_03
0625 w08 qp_03King Ali
 
0625_w12_qp_32
0625_w12_qp_320625_w12_qp_32
0625_w12_qp_32King Ali
 
0625 w02 qp_1
0625 w02 qp_10625 w02 qp_1
0625 w02 qp_1King Ali
 
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014JakKy Kitmanacharounpong
 
0580_w12_qp_41
0580_w12_qp_410580_w12_qp_41
0580_w12_qp_41King Ali
 
0625 s15 qp_32
0625 s15 qp_320625 s15 qp_32
0625 s15 qp_32Omniya Jay
 
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013JakKy Kitmanacharounpong
 
0620 w05 qp_3
0620 w05 qp_30620 w05 qp_3
0620 w05 qp_3King Ali
 
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paper
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paperSolved 0620 w16 qp_42-IGCSE Chemistry solved past paper
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paperSmart Exam Resources
 
0620 s09 qp_3
0620 s09 qp_30620 s09 qp_3
0620 s09 qp_3King Ali
 
0620 w13 qp_33
0620 w13 qp_330620 w13 qp_33
0620 w13 qp_33King Ali
 
0610 w07 qp_3
0610 w07 qp_30610 w07 qp_3
0610 w07 qp_3King Ali
 
0625 w09 qp_31
0625 w09 qp_310625 w09 qp_31
0625 w09 qp_31King Ali
 
0620_s05_qp_3
0620_s05_qp_30620_s05_qp_3
0620_s05_qp_3King Ali
 
0625 m15 qp_12
0625 m15 qp_120625 m15 qp_12
0625 m15 qp_12Omniya Jay
 
Cambridge Lower Secondary Checkpoint Past Paper P2 October-2017-science
Cambridge  Lower Secondary Checkpoint Past Paper P2 October-2017-scienceCambridge  Lower Secondary Checkpoint Past Paper P2 October-2017-science
Cambridge Lower Secondary Checkpoint Past Paper P2 October-2017-scienceSmart Exam Resources
 
0580_w10_qp_43
0580_w10_qp_430580_w10_qp_43
0580_w10_qp_43King Ali
 

Mais procurados (20)

0580_s14_qp_43
0580_s14_qp_430580_s14_qp_43
0580_s14_qp_43
 
0625_s14_qp_32
0625_s14_qp_320625_s14_qp_32
0625_s14_qp_32
 
Cambridge Lower Secondary Checkpoint Past Paper P2 october-2018-science
Cambridge  Lower Secondary Checkpoint Past Paper P2 october-2018-scienceCambridge  Lower Secondary Checkpoint Past Paper P2 october-2018-science
Cambridge Lower Secondary Checkpoint Past Paper P2 october-2018-science
 
0625 w08 qp_03
0625 w08 qp_030625 w08 qp_03
0625 w08 qp_03
 
0625_w12_qp_32
0625_w12_qp_320625_w12_qp_32
0625_w12_qp_32
 
0625 w02 qp_1
0625 w02 qp_10625 w02 qp_1
0625 w02 qp_1
 
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014
Physics 0625 - Paper 3 version 1 - Question Paper - May Jun 2014
 
0580_w12_qp_41
0580_w12_qp_410580_w12_qp_41
0580_w12_qp_41
 
0625 s15 qp_32
0625 s15 qp_320625 s15 qp_32
0625 s15 qp_32
 
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013
Physics 0625 - Paper 3 version 3 - Question Paper - May Jun 2013
 
0620 w05 qp_3
0620 w05 qp_30620 w05 qp_3
0620 w05 qp_3
 
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paper
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paperSolved 0620 w16 qp_42-IGCSE Chemistry solved past paper
Solved 0620 w16 qp_42-IGCSE Chemistry solved past paper
 
0620 s09 qp_3
0620 s09 qp_30620 s09 qp_3
0620 s09 qp_3
 
0620 w13 qp_33
0620 w13 qp_330620 w13 qp_33
0620 w13 qp_33
 
0610 w07 qp_3
0610 w07 qp_30610 w07 qp_3
0610 w07 qp_3
 
0625 w09 qp_31
0625 w09 qp_310625 w09 qp_31
0625 w09 qp_31
 
0620_s05_qp_3
0620_s05_qp_30620_s05_qp_3
0620_s05_qp_3
 
0625 m15 qp_12
0625 m15 qp_120625 m15 qp_12
0625 m15 qp_12
 
Cambridge Lower Secondary Checkpoint Past Paper P2 October-2017-science
Cambridge  Lower Secondary Checkpoint Past Paper P2 October-2017-scienceCambridge  Lower Secondary Checkpoint Past Paper P2 October-2017-science
Cambridge Lower Secondary Checkpoint Past Paper P2 October-2017-science
 
0580_w10_qp_43
0580_w10_qp_430580_w10_qp_43
0580_w10_qp_43
 

Destaque

0620 w11 qp_31
0620 w11 qp_310620 w11 qp_31
0620 w11 qp_31King Ali
 
IGCSE Chemistry revision guide 2012
IGCSE Chemistry revision guide 2012IGCSE Chemistry revision guide 2012
IGCSE Chemistry revision guide 2012mcdeena07
 
Chemistry revision pack_-_2012
Chemistry revision pack_-_2012Chemistry revision pack_-_2012
Chemistry revision pack_-_2012mcconvillezoe
 
0620_s14_qp_32
0620_s14_qp_320620_s14_qp_32
0620_s14_qp_32King Ali
 
0620_s11_qp_33
0620_s11_qp_330620_s11_qp_33
0620_s11_qp_33King Ali
 
0620_w11_qp_33
0620_w11_qp_330620_w11_qp_33
0620_w11_qp_33King Ali
 
0620 w12 qp_33
0620 w12 qp_330620 w12 qp_33
0620 w12 qp_33King Ali
 
0620 w13 qp_31
0620 w13 qp_310620 w13 qp_31
0620 w13 qp_31King Ali
 
0620 w06 qp_3
0620 w06 qp_30620 w06 qp_3
0620 w06 qp_3King Ali
 
0620 s06 ms_3
0620 s06 ms_30620 s06 ms_3
0620 s06 ms_3King Ali
 
0620_w08_qp_03
0620_w08_qp_030620_w08_qp_03
0620_w08_qp_03King Ali
 
0620 w13 qp_32
0620 w13 qp_320620 w13 qp_32
0620 w13 qp_32King Ali
 
0620 s06 qp_3
0620 s06 qp_30620 s06 qp_3
0620 s06 qp_3King Ali
 
0620 w02 qp_3
0620 w02 qp_30620 w02 qp_3
0620 w02 qp_3King Ali
 

Destaque (15)

0620 w11 qp_31
0620 w11 qp_310620 w11 qp_31
0620 w11 qp_31
 
IGCSE Chemistry revision guide 2012
IGCSE Chemistry revision guide 2012IGCSE Chemistry revision guide 2012
IGCSE Chemistry revision guide 2012
 
Chemistry revision pack_-_2012
Chemistry revision pack_-_2012Chemistry revision pack_-_2012
Chemistry revision pack_-_2012
 
0620_s14_qp_32
0620_s14_qp_320620_s14_qp_32
0620_s14_qp_32
 
0620_s11_qp_33
0620_s11_qp_330620_s11_qp_33
0620_s11_qp_33
 
0620_w11_qp_33
0620_w11_qp_330620_w11_qp_33
0620_w11_qp_33
 
0620 25
0620 250620 25
0620 25
 
0620 w12 qp_33
0620 w12 qp_330620 w12 qp_33
0620 w12 qp_33
 
0620 w13 qp_31
0620 w13 qp_310620 w13 qp_31
0620 w13 qp_31
 
0620 w06 qp_3
0620 w06 qp_30620 w06 qp_3
0620 w06 qp_3
 
0620 s06 ms_3
0620 s06 ms_30620 s06 ms_3
0620 s06 ms_3
 
0620_w08_qp_03
0620_w08_qp_030620_w08_qp_03
0620_w08_qp_03
 
0620 w13 qp_32
0620 w13 qp_320620 w13 qp_32
0620 w13 qp_32
 
0620 s06 qp_3
0620 s06 qp_30620 s06 qp_3
0620 s06 qp_3
 
0620 w02 qp_3
0620 w02 qp_30620 w02 qp_3
0620 w02 qp_3
 

Semelhante a 0620 27

Semelhante a 0620 27 (20)

0620 s13 qp_33
0620 s13 qp_330620 s13 qp_33
0620 s13 qp_33
 
0620 s03 qp_2
0620 s03 qp_20620 s03 qp_2
0620 s03 qp_2
 
0620 w14 qp_33
0620 w14 qp_330620 w14 qp_33
0620 w14 qp_33
 
0620 2
0620 20620 2
0620 2
 
0620 3
0620 30620 3
0620 3
 
0620 29
0620 290620 29
0620 29
 
0620 s03 qp_3
0620 s03 qp_30620 s03 qp_3
0620 s03 qp_3
 
0620 s03 qp_3
0620 s03 qp_30620 s03 qp_3
0620 s03 qp_3
 
0620 s03 qp_3
0620 s03 qp_30620 s03 qp_3
0620 s03 qp_3
 
0620 w13 qp_33
0620 w13 qp_330620 w13 qp_33
0620 w13 qp_33
 
0620 w15 qp_32
0620 w15 qp_320620 w15 qp_32
0620 w15 qp_32
 
0620 w13 qp_32
0620 w13 qp_320620 w13 qp_32
0620 w13 qp_32
 
0625_s14_qp_22
0625_s14_qp_220625_s14_qp_22
0625_s14_qp_22
 
0620 w11 qp_33
0620 w11 qp_330620 w11 qp_33
0620 w11 qp_33
 
9701 y16 sp_2 (1)
9701 y16 sp_2 (1)9701 y16 sp_2 (1)
9701 y16 sp_2 (1)
 
2016 chemistry paper 2 (specimen paper) (AS level structured questions)
2016 chemistry paper 2 (specimen paper) (AS level structured questions)2016 chemistry paper 2 (specimen paper) (AS level structured questions)
2016 chemistry paper 2 (specimen paper) (AS level structured questions)
 
0620 w12 qp_32
0620 w12 qp_320620 w12 qp_32
0620 w12 qp_32
 
0620 w12 qp_32
0620 w12 qp_320620 w12 qp_32
0620 w12 qp_32
 
0620 w12 qp_32
0620 w12 qp_320620 w12 qp_32
0620 w12 qp_32
 
0620 24
0620 240620 24
0620 24
 

Mais de King Ali

0510 w10 qp_21
0510 w10 qp_210510 w10 qp_21
0510 w10 qp_21King Ali
 
Friendship Poem by Haider Ali (1)
Friendship Poem by Haider Ali (1)Friendship Poem by Haider Ali (1)
Friendship Poem by Haider Ali (1)King Ali
 
Friendship Poem by Haider Ali (2)
Friendship Poem by Haider Ali (2)Friendship Poem by Haider Ali (2)
Friendship Poem by Haider Ali (2)King Ali
 
Hands and feet decorated paper
Hands and feet decorated paperHands and feet decorated paper
Hands and feet decorated paperKing Ali
 
Multicultural children decorated paper
Multicultural children decorated paperMulticultural children decorated paper
Multicultural children decorated paperKing Ali
 
0610_s04_qp_3
0610_s04_qp_30610_s04_qp_3
0610_s04_qp_3King Ali
 
0610_s06_qp_3
0610_s06_qp_30610_s06_qp_3
0610_s06_qp_3King Ali
 
Circular+(warning)+drinking+water
Circular+(warning)+drinking+waterCircular+(warning)+drinking+water
Circular+(warning)+drinking+waterKing Ali
 
0620_w08_qp_2
0620_w08_qp_20620_w08_qp_2
0620_w08_qp_2King Ali
 
0620_w05_qp_6
0620_w05_qp_60620_w05_qp_6
0620_w05_qp_6King Ali
 
0610_s14_qp_33
0610_s14_qp_330610_s14_qp_33
0610_s14_qp_33King Ali
 
5125_w03_qp_04
5125_w03_qp_045125_w03_qp_04
5125_w03_qp_04King Ali
 
0610_w11_qp_22
0610_w11_qp_220610_w11_qp_22
0610_w11_qp_22King Ali
 
0625_w14_qp_11
0625_w14_qp_110625_w14_qp_11
0625_w14_qp_11King Ali
 
0625_w13_qp_12
0625_w13_qp_120625_w13_qp_12
0625_w13_qp_12King Ali
 
0625_s06_qp_1
0625_s06_qp_10625_s06_qp_1
0625_s06_qp_1King Ali
 
0625_w12_qp_11
0625_w12_qp_110625_w12_qp_11
0625_w12_qp_11King Ali
 
0625_w11_qp_11
0625_w11_qp_110625_w11_qp_11
0625_w11_qp_11King Ali
 
0625_s14_qp_11
0625_s14_qp_110625_s14_qp_11
0625_s14_qp_11King Ali
 
0625_s14_qp_12
0625_s14_qp_120625_s14_qp_12
0625_s14_qp_12King Ali
 

Mais de King Ali (20)

0510 w10 qp_21
0510 w10 qp_210510 w10 qp_21
0510 w10 qp_21
 
Friendship Poem by Haider Ali (1)
Friendship Poem by Haider Ali (1)Friendship Poem by Haider Ali (1)
Friendship Poem by Haider Ali (1)
 
Friendship Poem by Haider Ali (2)
Friendship Poem by Haider Ali (2)Friendship Poem by Haider Ali (2)
Friendship Poem by Haider Ali (2)
 
Hands and feet decorated paper
Hands and feet decorated paperHands and feet decorated paper
Hands and feet decorated paper
 
Multicultural children decorated paper
Multicultural children decorated paperMulticultural children decorated paper
Multicultural children decorated paper
 
0610_s04_qp_3
0610_s04_qp_30610_s04_qp_3
0610_s04_qp_3
 
0610_s06_qp_3
0610_s06_qp_30610_s06_qp_3
0610_s06_qp_3
 
Circular+(warning)+drinking+water
Circular+(warning)+drinking+waterCircular+(warning)+drinking+water
Circular+(warning)+drinking+water
 
0620_w08_qp_2
0620_w08_qp_20620_w08_qp_2
0620_w08_qp_2
 
0620_w05_qp_6
0620_w05_qp_60620_w05_qp_6
0620_w05_qp_6
 
0610_s14_qp_33
0610_s14_qp_330610_s14_qp_33
0610_s14_qp_33
 
5125_w03_qp_04
5125_w03_qp_045125_w03_qp_04
5125_w03_qp_04
 
0610_w11_qp_22
0610_w11_qp_220610_w11_qp_22
0610_w11_qp_22
 
0625_w14_qp_11
0625_w14_qp_110625_w14_qp_11
0625_w14_qp_11
 
0625_w13_qp_12
0625_w13_qp_120625_w13_qp_12
0625_w13_qp_12
 
0625_s06_qp_1
0625_s06_qp_10625_s06_qp_1
0625_s06_qp_1
 
0625_w12_qp_11
0625_w12_qp_110625_w12_qp_11
0625_w12_qp_11
 
0625_w11_qp_11
0625_w11_qp_110625_w11_qp_11
0625_w11_qp_11
 
0625_s14_qp_11
0625_s14_qp_110625_s14_qp_11
0625_s14_qp_11
 
0625_s14_qp_12
0625_s14_qp_120625_s14_qp_12
0625_s14_qp_12
 

Último

UiPath Studio Web workshop series - Day 8
UiPath Studio Web workshop series - Day 8UiPath Studio Web workshop series - Day 8
UiPath Studio Web workshop series - Day 8DianaGray10
 
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1DianaGray10
 
Videogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfVideogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfinfogdgmi
 
Introduction to Matsuo Laboratory (ENG).pptx
Introduction to Matsuo Laboratory (ENG).pptxIntroduction to Matsuo Laboratory (ENG).pptx
Introduction to Matsuo Laboratory (ENG).pptxMatsuo Lab
 
Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024SkyPlanner
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPathCommunity
 
Nanopower In Semiconductor Industry.pdf
Nanopower  In Semiconductor Industry.pdfNanopower  In Semiconductor Industry.pdf
Nanopower In Semiconductor Industry.pdfPedro Manuel
 
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...UbiTrack UK
 
20230202 - Introduction to tis-py
20230202 - Introduction to tis-py20230202 - Introduction to tis-py
20230202 - Introduction to tis-pyJamie (Taka) Wang
 
Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1DianaGray10
 
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdf
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdf
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdfJamie (Taka) Wang
 
VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXTarek Kalaji
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Websitedgelyza
 
AI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarAI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarPrecisely
 
Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Adtran
 
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IES VE
 
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...DianaGray10
 
Artificial Intelligence & SEO Trends for 2024
Artificial Intelligence & SEO Trends for 2024Artificial Intelligence & SEO Trends for 2024
Artificial Intelligence & SEO Trends for 2024D Cloud Solutions
 

Último (20)

UiPath Studio Web workshop series - Day 8
UiPath Studio Web workshop series - Day 8UiPath Studio Web workshop series - Day 8
UiPath Studio Web workshop series - Day 8
 
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1UiPath Platform: The Backend Engine Powering Your Automation - Session 1
UiPath Platform: The Backend Engine Powering Your Automation - Session 1
 
Videogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdfVideogame localization & technology_ how to enhance the power of translation.pdf
Videogame localization & technology_ how to enhance the power of translation.pdf
 
Introduction to Matsuo Laboratory (ENG).pptx
Introduction to Matsuo Laboratory (ENG).pptxIntroduction to Matsuo Laboratory (ENG).pptx
Introduction to Matsuo Laboratory (ENG).pptx
 
Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024Salesforce Miami User Group Event - 1st Quarter 2024
Salesforce Miami User Group Event - 1st Quarter 2024
 
UiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation DevelopersUiPath Community: AI for UiPath Automation Developers
UiPath Community: AI for UiPath Automation Developers
 
Nanopower In Semiconductor Industry.pdf
Nanopower  In Semiconductor Industry.pdfNanopower  In Semiconductor Industry.pdf
Nanopower In Semiconductor Industry.pdf
 
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...
UWB Technology for Enhanced Indoor and Outdoor Positioning in Physiological M...
 
20230202 - Introduction to tis-py
20230202 - Introduction to tis-py20230202 - Introduction to tis-py
20230202 - Introduction to tis-py
 
Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1Secure your environment with UiPath and CyberArk technologies - Session 1
Secure your environment with UiPath and CyberArk technologies - Session 1
 
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdf
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdf
activity_diagram_combine_v4_20190827.pdfactivity_diagram_combine_v4_20190827.pdf
 
201610817 - edge part1
201610817 - edge part1201610817 - edge part1
201610817 - edge part1
 
VoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBXVoIP Service and Marketing using Odoo and Asterisk PBX
VoIP Service and Marketing using Odoo and Asterisk PBX
 
20230104 - machine vision
20230104 - machine vision20230104 - machine vision
20230104 - machine vision
 
COMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a WebsiteCOMPUTER 10 Lesson 8 - Building a Website
COMPUTER 10 Lesson 8 - Building a Website
 
AI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity WebinarAI You Can Trust - Ensuring Success with Data Integrity Webinar
AI You Can Trust - Ensuring Success with Data Integrity Webinar
 
Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™Meet the new FSP 3000 M-Flex800™
Meet the new FSP 3000 M-Flex800™
 
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
IESVE Software for Florida Code Compliance Using ASHRAE 90.1-2019
 
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...
Connector Corner: Extending LLM automation use cases with UiPath GenAI connec...
 
Artificial Intelligence & SEO Trends for 2024
Artificial Intelligence & SEO Trends for 2024Artificial Intelligence & SEO Trends for 2024
Artificial Intelligence & SEO Trends for 2024
 

0620 27

  • 1. UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education *4888728650* CHEMISTRY 0620/32 Paper 3 (Extended) October/November 2011 1 hour 15 minutes Candidates answer on the Question Paper. No Additional Materials are required. READ THESE INSTRUCTIONS FIRST Write your Centre number, candidate number and name on all the work you hand in. Write in dark blue or black pen. You may use a pencil for any diagrams, graphs or rough working. Do not use staples, paper clips, highlighters, glue or correction fluid. DO NOT WRITE IN ANY BARCODES. Answer all questions. A copy of the Periodic Table is printed on page 12. 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. For Examiner’s Use 1 2 3 4 5 6 7 Total This document consists of 12 printed pages. IB11 11_0620_32/2RP © UCLES 2011 [Turn over
  • 2. 2 1 For Examiner’s Use Cobalt is an element in Period 4 of the Periodic Table. (a) Use your copy of the Periodic Table to help you complete the table below. particle number of protons number of neutrons number of electrons Co Co2+ [2] (b) 60 Co is a cobalt isotope. (i) Explain the term isotope. .................................................................................................................................... .................................................................................................................................... .............................................................................................................................. [2] (ii) Explain why two isotopes of the same element have identical chemical properties. .............................................................................................................................. [1] (iii) State one industrial use and one medical use of radioactive isotopes. industrial use ....................................................................................................... [1] medical use ......................................................................................................... [1] [Total: 7] © UCLES 2011 0620/32/O/N/11
  • 3. 3 2 For Examiner’s Use Sulfur is needed for the production of sulfuric acid. Two of the major sources of sulfur are ● underground deposits of the element sulfur, ● sulfur compounds from natural gas and petroleum. (a) Explain why sulfur and its compounds are removed from these fuels before they are burned. ........................................................................................................................................... ..................................................................................................................................... [2] (b) Sulfur dioxide is made by spraying molten sulfur into air. The sulfur ignites and sulfur dioxide is formed. (i) Suggest why molten sulfur is used in the form of a fine spray. .................................................................................................................................... .............................................................................................................................. [2] (ii) Explain why traces of sulfur dioxide act as a preservative in fruit juices. .............................................................................................................................. [1] (iii) State another use of sulfur dioxide. .............................................................................................................................. [1] (c) Describe how sulfur dioxide is changed into sulfur trioxide. Give the reaction conditions and an equation. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [4] (d) Complete the following equations for the formation of sulfuric acid from sulfur trioxide. SO3 + ............... → H2S2O7 H2S2O7 + ………. → ..........H2SO4 [2] [Total: 12] © UCLES 2011 0620/32/O/N/11 [Turn over
  • 4. 4 3 For Examiner’s Use Antimony, Sb, is an element in Group V. (a) The main ore of antimony is its sulfide. The extraction of antimony is similar to that of zinc. Describe how each of these changes in the extraction of antimony is carried out. (i) antimony sulfide to antimony oxide .............................................................................................................................. [1] (ii) antimony oxide to antimony .............................................................................................................................. [1] (b) Antimony oxide is a white powder which is insoluble in water. Describe how you would find out if it is a basic, an acidic or an amphoteric oxide. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [4] (c) When antimony chloride is added to water, a faint white precipitate forms and the mixture slowly goes cloudy. forward SbCl 3(aq) + H2O(l) colourless 2HCl (aq) + SbOCl (s) backward white (i) Explain why after some time the appearance of the mixture remains unchanged. .................................................................................................................................... .............................................................................................................................. [2] (ii) When a few drops of concentrated hydrochloric acid are added to the mixture, it changes to a colourless solution. Suggest an explanation. .................................................................................................................................... .............................................................................................................................. [1] (iii) Suggest how you could make the colourless solution go cloudy. .............................................................................................................................. [1] [Total: 10] © UCLES 2011 0620/32/O/N/11
  • 5. 5 4 For Examiner’s Use The structure of an element or compound determines its physical properties. Scandium fluoride and silicon(IV) oxide have giant structures. (a) Scandium fluoride is an ionic compound. (i) The valency of scandium is three. Draw a diagram which shows the formula of the compound, the charges on the ions and the arrangement of the valency electrons around the negative ion. Use x to represent an electron from a scandium atom. Use o to represent an electron from a fluorine atom. [3] (ii) The melting point of scandium fluoride is 1552 °C. Explain why scandium fluoride has a high melting point. .................................................................................................................................... .............................................................................................................................. [1] (b) Silicon(IV) oxide has a macromolecular structure. (i) Describe the structure of silicon(IV) oxide. You may use a diagram. [3] (ii) How does the electrical conductivity of these two compounds differ? .................................................................................................................................... .............................................................................................................................. [1] (iii) Explain the difference in conductivity. .................................................................................................................................... .............................................................................................................................. [2] [Total: 10] © UCLES 2011 0620/32/O/N/11 [Turn over
  • 6. 6 5 The alcohols form a homologous series. Two characteristics of a homologous series are that the physical properties of the members vary in a predictable way and they have similar chemical properties. (a) Complete the table. name mass of one mole / g formula boiling point / °C methanol CH3 – OH 32 64 ethanol CH3 – CH2 – OH 46 78 propan-1-ol CH3 – CH2 – CH2 – OH 60 98 butan-1-ol CH3 – CH2 – CH2 – CH2 – OH 74 118 pentan-1-ol hexan-1-ol 138 CH3 – CH2 – CH2 – CH2 – CH2 – CH2 – OH 102 [3] (b) Give two other characteristics of a homologous series. ........................................................................................................................................... ..................................................................................................................................... [2] (c) Draw a diagram showing the arrangement of the valency electrons in one molecule of the covalent compound methanol. Use x to represent an electron from a carbon atom. Use o to represent an electron from an oxygen atom. Use ● to represent an electron from a hydrogen atom. [3] © UCLES 2011 0620/32/O/N/11 For Examiner’s Use
  • 7. 7 (d) Alcohols can be oxidised to carboxylic acids by heating with acidic potassium manganate(VII). For Examiner’s Use (i) Draw the structural formula of the carboxylic acid formed by the oxidation of propan-1-ol. Show all the bonds. [1] (ii) Describe how ethanol could be oxidised to ethanoic acid by fermentation. .................................................................................................................................... .............................................................................................................................. [2] (e) Propan-1-ol and ethanoic acid react together to form an ester. Give its name and structural formula. name ........................................................................................................................... [1] formula [1] [Total: 13] © UCLES 2011 0620/32/O/N/11 [Turn over
  • 8. 8 6 Soluble salts can be made by the neutralisation of an acid by a base. Insoluble salts can be made by precipitation. (a) The following is a brief description of the preparation of the soluble salt, nickel(II) chloride-6-water, from the insoluble base nickel(II) carbonate. Nickel(II) carbonate is added in small amounts to hot dilute hydrochloric acid until it is in excess. The mixture is filtered. The filtrate is partially evaporated and then allowed to cool until crystals of nickel(II) chloride-6-water form. (i) Why is it necessary to use excess carbonate? .................................................................................................................................... .............................................................................................................................. [1] (ii) Explain why it is necessary to filter. .............................................................................................................................. [1] (iii) Why partially evaporate rather than evaporate to dryness? .................................................................................................................................... .............................................................................................................................. [1] (iv) What additional steps are needed to obtain dry crystals? .................................................................................................................................... .............................................................................................................................. [2] (b) Potassium chloride can be made from hydrochloric acid and potassium carbonate. (i) Why must a different experimental method be used for this preparation? .................................................................................................................................... .............................................................................................................................. [1] (ii) Give a description of the different method used for this salt preparation. .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .............................................................................................................................. [4] © UCLES 2011 0620/32/O/N/11 For Examiner’s Use
  • 9. 9 (c) Insoluble salts are made by precipitation. An equation for the preparation of barium sulfate is given below. For Examiner’s Use BaCl 2(aq) + MgSO4(aq) → BaSO4(s) + MgCl 2(aq) This reaction can be used to find x in the formula for hydrated magnesium sulfate MgSO4.xH2O. A known mass of hydrated magnesium sulfate, MgSO4.xH2O, was dissolved in water. Excess aqueous barium chloride was added. The precipitate of barium sulfate was filtered, washed and dried. Finally it was weighed. Mass of hydrated magnesium sulfate = 1.476 g Mass of barium sulfate formed = 1.398 g The mass of one mole of BaSO4 = 233 g The number of moles of BaSO4 formed = ............... [1] The number of moles of MgSO4.xH2O = ............... [1] The mass of one mole of MgSO4.xH2O = ............... g [1] The mass of one mole of MgSO4 = 120 g The mass of xH2O in one mole of MgSO4.xH2O = ............... [1] x = ............... [1] [Total: 15] © UCLES 2011 0620/32/O/N/11 [Turn over
  • 10. 10 7 Petrol is a mixture of hydrocarbons and additives. The combustion of petrol in car engines is a major source of air pollution. This is reduced by catalytic converters. (a) Petrol is obtained from the gasoline fraction, boiling point range 40 °C to 100 °C, from the distillation of petroleum. Explain the term fraction. ........................................................................................................................................... ..................................................................................................................................... [2] (b) In many countries, a lead compound of the type Pb(C2H5)n used to be added to petrol to improve its combustion. After combustion, lead oxide was formed. LEADED 98 OCTANE (i) Octane is a constituent of petrol. Write the equation for the complete combustion of octane. C8H18 + ...............O2 → ............... + ............... [2] (ii) Dibromoethane was added to petrol to remove the lead oxide from inside the engine. Lead bromide was formed which escaped into the environment through the exhaust. Leaded petrol cannot be used with a catalytic converter. Give another reason why leaded petrol is no longer used. .............................................................................................................................. [1] (iii) What does each of the following tell you about the structure of dibromoethane? dibromo ...................................................................................................................... eth .............................................................................................................................. ane ....................................................................................................................... [2] (iv) What additional information is needed to draw the structural formula of dibromoethane? .............................................................................................................................. [1] © UCLES 2011 0620/32/O/N/11 For Examiner’s Use
  • 11. 11 (c) An analysis of the compound, Pb(C2H5)n , showed that 0.026 moles of Pb was combined with 0.104 moles of C2H5 groups. What is the value of n? Show how you arrived at your answer. ........................................................................................................................................... ..................................................................................................................................... [2] (d) Some of the pollutants emitted by vehicle exhausts are carbon monoxide, oxides of nitrogen and unburnt hydrocarbons. Explain how the emission of these gases is reduced by a catalytic converter. ........................................................................................................................................... ........................................................................................................................................... ..................................................................................................................................... [3] [Total: 13] © UCLES 2011 0620/32/O/N/11 For Examiner’s Use
  • 12. © UCLES 2011 24 40 Sodium Calcium 88 0620/32/O/N/11 89 Key b X a 72 b = proton (atomic) number X = atomic symbol a = relative atomic mass *58-71 Lanthanoid series 90-103 Actinoid series 88 Ac Actinium Ra Radium Fr Francium 87 * Hafnium Lanthanum 57 Hf La 40 Zirconium Zr 91 Titanium 178 Yttrium 22 48 Ti 139 39 Y 89 Scandium 21 227 Caesium 56 Barium Cs 45 Sc 226 55 137 Ba 133 Strontium Rubidium 38 Rb 37 Sr 85 20 Potassium 19 Ca 39 Magnesium Na 12 Mg 23 Beryllium 4 Lithium K 11 3 9 Be 7 II Li I 51 93 Ta 181 Niobium Nb 90 58 73 52 96 Mo W 184 141 Pa Thorium 55 Tc 186 Re 144 Nd 92 60 Uranium U 238 Neodymium 75 Rhenium 43 Technetium 25 Manganese Mn 29 30 65 8 9 VII 2 0 Ru 101 Iron 190 Pm Osmium Os 93 Np Neptunium 61 Promethium 76 44 Ruthenium 26 56 Fe 192 Sm 150 Iridium Ir 94 Pu Plutonium 62 Samarium 77 45 Rhodium Rh 103 Cobalt Co 195 Eu 152 Platinum Pt 95 Am Americium 63 Europium 78 46 Palladium Pd 106 Nickel Ni Gd 157 Gold Au 197 Silver 96 64 Curium Cm Gadolinium 79 47 Ag 108 Copper Cu 201 Bk Terbium Tb 159 Mercury Hg 97 Berkelium 65 80 48 Cadmium Cd 112 Zinc Zn 11 70 Dy 162 Thallium Tl 204 Indium In 115 Gallium Ga 98 Cf Californium 66 Dysprosium 81 49 31 13 Aluminium 119 Es Holmium Ho 165 Lead Pb 207 Tin Sn 99 Einsteinium 67 82 50 32 Germanium Ge 73 Silicon Si Al 14 28 Carbon 27 Boron 12 C 14 75 Sb 122 Arsenic As Bi 209 Fermium Fm Erbium Er 167 Bismuth 100 68 83 51 Antimony 33 15 Phosphorus P 31 Nitrogen N Se 79 Sulfur S 32 Oxygen Po 169 Md Thulium Tm 101 Mendelevium 69 84 Polonium 52 Tellurium Te 128 Selenium 34 16 16 O Yb 173 Astatine At Iodine I 127 Bromine Br 80 Chlorine No 102 Nobelium 70 Ytterbium 85 53 35 17 Cl 35.5 Fluorine F 19 Lr Lutetium Lu 175 Radon Rn Xenon Xe 131 Krypton Kr 84 Argon Ar 40 Neon 103 Lawrencium 71 86 54 36 18 10 Ne 20 Helium Hydrogen B 4 28 64 7 VI He 27 59 6 V H 59 5 IV The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.). 91 Protactinium Th 232 Praseodymium Cerium 59 Pr Ce 74 Tungsten 42 Molybdenum 24 Chromium Cr 140 Tantalum 41 23 Vanadium V 1 III 1 Group DATA SHEET The Periodic Table of the Elements 12 Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included the publisher will be pleased to make amends at the earliest possible opportunity. University of Cambridge International Examinations is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.