VP*(S10-245-02)
ADDITIONAL MATERIALS
In addition to this paper you may require a calculator and a ruler.
INSTRUCTIONS TO CANDIDATES
Write your name, centre number and candidate number in the spaces at the top of this page.
Answer all questions.
Write your answers in the spaces provided in this booklet.
INFORMATION FOR CANDIDATES
The number of marks is given in brackets at the end of each question or part-question.
You are reminded of the necessity for good English and orderly presentation in your answers.
The Periodic Table is printed on the back cover of the examination paper and the formulae for some common ions on the inside of the back cover.
GCSE 245/02
SCIENCE CHEMISTRY
HIGHER TIER CHEMISTRY 3
A.M. WEDNESDAY, 26 May 2010 45 minutes
Candidate Name
Candidate Number Centre
Number
0
For Examiner’s use only
Question Maximum
Mark
Mark Awarded
1. 7
4 4 10
8 9 5 3 2.
3.
4.
5.
6.
7.
8.
50 Total
0245 0201
(245-02) Answer allquestions.
1.(a)The equation below represents the preparation of ethanol from glucose solution, in thepresence of yeast.
C6H12O62C2H5OH + 2CO2
(i)Write the word equation to represent the reaction above.[2]
......+ ...
(ii)Give the term for the process taking place when ethanol is formed from glucosesolution.[1]
...
(b)Once the reaction stops, the unreacted yeast can be removed by filtering to recover amixture of unreacted glucose solution and ethanol.
The diagram below shows the apparatus which could then be used to separate ethanolfrom the unreacted glucose solution. 2Examiner
(i)Give the reason why the ethanol can be separated from the unreacted glucosesolution by this method.[1]
...... A thermometer
flask
unreactedglucose solutionand ethanolmixture water out
cold water in
Turn over. 3Examineronly
(ii)Give the nameof
I.the process being used to obtain ethanol from the mixture,[1]
...
II.the change of state occurring in the flask,[1]
...
III.the change of state occurring in apparatus A.[1]
...
7
0 2 4 5 0 2 0 3
(245-02) 4Examiner
2.The temperature ranges for which enzyme activityoccurs can be different for differentenzymes.
The graph below shows the amountof activity of an enzyme, A, over a temperature range.
(i)Use the graph to give the temperature when the amount of enzyme activity is greatestfor enzyme A.[1]
...°C
(ii)Sketch carefully the graph of the enzyme activity of a different enzyme, B, which isactive between 0 and 55°C and has its greatest activity at 30°C.[2]
(iii)Give a temperature value at which bothenzymes would be inactive.[1]
...°C 0102030405060 A
–10
Temperature / °C Amount ofenzyme activity
Turn over. 5Examineronly
The diagram below shows the apparatus used to investigate the different dyes in five felttipped pens, A, B, C, Dand E.
The following chromatograms were obtained from the five different coloured pens.
(i)Give the letterof the pen which contains
I.boththe dyes found in pen D, ...[1]
II.the dyes found in bothpens Band C. ...[1]
(ii)Pencils made from graphite are usually used to draw the reference line on the strips offilter paper used in chromatography experiments.
Give the property of graphite that makes a pencil a more suitable choice than ink, fordrawing reference lines.[1]
...
(iii)Describe how you would find the originalcolour of pen Afrom its chromatogram.[1]
......
4 water
ABCDE separated dyes strip of filter paper
pen colour on reference line
0 2 4 5 0 2 0 5
(245-02) 6Examiner
4.(a)The flow diagram below shows the reactions that occur to prepare slaked lime,Ca(OH)2, from limestone, CaCO3.
Reaction1
CaCO3CaO + gas BCa(OH)2 Reaction2
Process AAdd a few dropsof liquid C
(i)I.Give the term for the breakdown of calcium carbonate in Reaction 1.[1]
......
II.State what needs to be done to limestone for this to happen.[1]
......
(ii)Give the name of
I.gas B, ...[1]
II.liquid C. ...[1]
(iii)Write a balancedsymbolequation for Reaction 2.[3]
...+ ......
(b)Name the metallic elementwhich uses limestone during its extraction.[1]
...
(c)Give two disadvantages associated with limestone quarrying.[2]
1. ......
2. ......
10
Turn over. 7
BLANK P A GE
0 2 4 5 0 2 0 7
(245-02) 5.(a)The molecular formulae of five carbon compounds are shown below.
C3H6C4H10C3H8C2H5OH CH3OH
ABCDE
(i)Give the lettersof twocarbon compounds which belong to the alkane homologousseries.[1]
...and ...
(ii)Give the letterof the carbon compound which has the structural formula
HCCC H
H H
H H
Letter...[1]
(b)Butane, C4H10, has two chain isomers.
(i)Draw the structures of both chain isomers of butane.[2]
(ii)Use your structures to explain the meaning of the term isomer.[1]
......
...... 8Examiner
Turn over. 9Examineronly
(c)The flow diagram below shows two reactions of ethene.
HCC
H H H
H H
CC H
H H
H X
(i)Give the chemical namefor
I.gas G, ... [1]
II.the product of the reaction between ethene and gas G.
... [1]
(ii)Draw the structural formulafor compound X, formed whenethene reacts withbromine.[1]
8 Br2
ethene gas G
(245-02) 10Examiner
6.The main stages in the manufacture of sulphuric acid are given below.
Stage 1:Sulphur reacts with oxygen.
Stage 2:Sulphur dioxide reacts with oxygen.
Stage 3:Sulphur trioxide is absorbed into concentrated sulphuric acid and diluted tovarious concentrations.
(i)Give the name of the raw materialthat is used in both stages1and 2.[1]
...
(ii)During Stage 2, gases are passed through a vanadium(V) oxide catalyst. The catalystwill notwork below 400°C and breaks downabove 620°C.
The table below shows the % yield of sulphur trioxide at different temperatures in Stage 2.
Temperature / °C
% Yield of sulphur trioxide 400450500550600
9997928576
Turn over. 11Examineronly
Plot a graph of the % yield of sulphur trioxide at different temperatures, on the gridbelow.[3]
40350400450500550600650 50 60 70 80 90 100
% Yield ofsulphur trioxide
Temperature / °C
(iii)Use the graph to
I.state how changing the temperature affects the % yield of sulphur trioxide,[1]
......
II.give the temperature rangeto be used to obtain a yield of sulphur trioxide above90%.[1]
...to ...°C
(iv)Write a balancedsymbolequation for the reaction between sulphur dioxide and oxygen,O2, in Stage 2.[3]
...+ ......
9
(245-02) 12Examiner
7.The diagram below shows the apparatus used to find the concentration of a sample of diluteethanoic acid.
apparatus A
dilute ethanoic acid
20.0cm 3sodium hydroxide solution and 3 drops of indicator
The acid was added a little at a time, using apparatus A. The volume of acid needed to changethe indicator colour was recorded. The titration was repeated a number of times and anaverage volume of acid calculated.
(i)Name the piece of apparatus labelled Ain the diagram. ... [1]
(ii)State the purpose of the indicator.[1]
......
......
(iii)Ethanoic acid reacts with sodium hydroxide solution according to the equation below.
CH3COOH + NaOH CH3COONa + H2O It was found that 25.0cm 3of dilute ethanoic acid was needed to neutralise 20.0cm 3ofsodium hydroxide solution of concentration 0.25moldm –3.
Calculate the concentration of the acid in moldm –3.[3]
......
......
......
...Concentration= ...moldm –3
Turn over. 13Examineronly
The flow charts below show tests carried out by Duncan on compounds A, Band Cand theresults of those tests.
The compounds were known to include some of the following ions.
white precipitateformed Add dilutehydrochloric acidfollowed by bariumchloride solution.Flame test
CompoundA yellowcoloured flame
cream precipitateformed Add dilute nitricacid followed bysilver nitratesolution.Flame test
CompoundB lilaccoloured flame gas given off,turns limewatermilky Add dilutehydrochloric acid.Bubble gas given off into limewater. Add sodium hydroxidesolution and warm themixture. Test the gas given off with damp litmus.CompoundC pungent smelling gas given off, turnsdamp litmus paper blue
Use the information above to identify compounds A, Band C.[3]
Compound Ais ...
Compound Bis ...
Compound Cis ...
3 ammonium calcium potassium sodium
bromide carbonate iodide sulphate
(245-02)
BLANK P A GE
14FORMULAE FOR SOME COMMON IONS
POSITIVE IONS
NameFormula NEGATIVE IONS
NameFormula
AluminiumAl 3+
AmmoniumNH +
BariumBa 2+
CalciumCa 2+
Copper(II)Cu 2+
HydrogenH +
Iron(II)Fe 2+
Iron(III)Fe 3+
LithiumLi +
MagnesiumMg 2+
NickelNi 2+
PotassiumK +
SilverAg +
SodiumNa + BromideBr –
CarbonateCO 2–
ChlorideCl –
FluorideF –
HydroxideOH –
IodideI –
NitrateNO –
OxideO 2–
SulphateSO 2– 4
4 3 3
Turn over. 15
Helium
Neon Fluorine
Chlorine
Bromine Selenium
Boron
Aluminium
Gallium Zinc
Copper Nickel
Cobalt Iron
Manganese Chromium
Vanadium Titanium
Scandium Calcium
Potassium
Magnesium Sodium
Beryllium Lithium
Arsenic Phosphorus
Nitrogen Carbon
Silicon
Germanium
Sulphur Oxygen
Argon
Krypton
4 2
20 Ne F 10
19
O 9 16
C 8 12
6 147 N
11 B
5
40Ar S 18
32
P 16 31
Si 15 28
Al 14 27 13
84Kr Br 36
80
Se 35 79
As 34 75
Ge 33 73
Ga 32 70
Zn 31 65
Cu 30 64
Ni 29 59
Fe 28 56
26 5927Co
55Mn V 25
51
23 5224Cr
48Ti Sc 22 45
Ca 21 40
K 20 39 19
Iodine Tellurium
Indium Cadmium
Silver Palladium Rhodium
Ruthenium Molybdenum
Niobium Zirconium
Yttrium Strontium
Rubidium Tin Antimony Xenon
131Xe I 54 127
Te 53 128
Sb 52 122
Sn 51 119
In 50 115
Cd 49 112
Ag 48 108
Pd 47 106
Ru 46 101
44 10345 Rh
99 Tc Nb 43
93
41 9642Mo
91Zr Y 40 89
Sr 39 88
Rb 38 86 37
Astatine Polonium
Thallium Mercury
Gold Platinum Iridium
Osmium Rhenium
Tungsten Tantalum
Hafnium Lanthanum
Barium
Caesium Lead Bismuth Radon
222Rn At 86 210
Po 85 210
Bi 84 209
Pb 83 207
Tl 82 204
Hg 81 201
Au 80 197
Pt 79 195
Os 78 190
76 19277 Ir
186 Re Ta 75
181
73 18474 W
179Hf La 72 139
Ba 57 137
Cs 56 133
55
Actinium Radium
Francium
227Ac Ra 89 226
Fr 88 223
87
24Mg Na 12
23 11
9 Be Li 4
7 3
Hydrogen
1 H
1
1 2 Group 3 4 5 6 7 0
PERIODIC TABLE OF ELEMENTS
He
35Cl
17
Z X A
Name
Element Symbol Atomic number
Mass number Key:
Technetium
(245-02) 16
