Published - Max Papers | Ultimate resource for …maxpapers.com/wp-content/uploads/2012/11/0620_s17_ms_all.pdfCHEMISTRY 0620/11 Paper 1 Multiple Choice (Core) May/June 2017 MARK SCHEME

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Cambridge International Examinations Cambridge International General Certificate of Secondary Education

CHEMISTRY 0620/11 Paper 1 Multiple Choice (Core) May/June 2017

MARK SCHEME

Maximum Mark: 40

Published

This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the May/June 2017 series for most Cambridge IGCSE®, Cambridge International A and AS Level and Cambridge Pre-U components, and some Cambridge O Level components.

0620/11 Cambridge IGCSE – Mark Scheme PUBLISHED

May/June 2017

© UCLES 2017 Page 2 of 3

Question Answer Marks

1 B 1

2 B 1

3 C 1

4 B 1

5 B 1

6 C 1

7 B 1

8 C 1

9 A 1

10 A 1

11 B 1

12 C 1

13 C 1

14 D 1

15 A 1

16 B 1

17 A 1

18 C 1

19 C 1

20 D 1

21 D 1

22 A 1

23 D 1

24 D 1

25 B 1

26 B 1

27 B 1

28 C 1


May/June 2017



29 A 1

30 A 1

31 C 1

32 C 1

33 D 1

34 D 1

35 C 1

36 B 1

37 D 1

38 A 1

39 D 1

40 C 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1 B 1

2 B 1

3 C 1

4 B 1

5 D 1

6 C 1

7 A 1

8 B 1

9 C 1

10 B 1

11 B 1

12 C 1

13 A 1

14 B 1

15 A 1

16 B 1

17 C 1

18 A 1

19 C 1

20 A 1

21 C 1

22 A 1

23 D 1

24 D 1

25 B 1

26 D 1

27 B 1

28 C 1


May/June 2017



29 A 1

30 D 1

31 B 1

32 C 1

33 C 1

34 D 1

35 D 1

36 A 1

37 C 1

38 B 1

39 C 1

40 C 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1 B 1

2 D 1

3 D 1

4 B 1

5 D 1

6 D 1

7 C 1

8 C 1

9 C 1

10 A 1

11 D 1

12 C 1

13 B 1

14 C 1

15 A 1

16 B 1

17 B 1

18 D 1

19 C 1

20 C 1

21 C 1

22 A 1

23 D 1

24 D 1

25 B 1

26 C 1

27 B 1

28 C 1

29 A 1


May/June 2017



30 B 1

31 B 1

32 C 1

33 C 1

34 D 1

35 B 1

36 B 1

37 A 1

38 C 1

39 D 1

40 C 1






CHEMISTRY 0620/21 Paper 2 Multiple Choice (Extended) May/June 2017

MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1 D 1

2 C 1

3 D 1

4 B 1

5 C 1

6 D 1

7 B 1

8 A 1

9 B 1

10 B 1

11 B 1

12 C 1

13 B 1

14 C 1

15 A 1

16 C 1

17 D 1

18 A 1

19 C 1

20 D 1

21 D 1

22 A 1

23 C 1

24 D 1

25 A 1

26 B 1

27 C 1

28 C 1


May/June 2017



29 A 1

30 D 1

31 D 1

32 C 1

33 C 1

34 D 1

35 C 1

36 C 1

37 C 1

38 C 1

39 B 1

40 C 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1 D 1

2 C 1

3 A 1

4 A 1

5 B 1

6 B 1

7 B 1

8 A 1

9 B 1

10 B 1

11 B 1

12 C 1

13 B 1

14 A 1

15 A 1

16 A 1

17 D 1

18 B 1

19 B 1

20 A 1

21 A 1

22 A 1

23 B 1

24 D 1

25 D 1

26 B 1

27 C 1

28 C 1


May/June 2017



29 A 1

30 C 1

31 A 1

32 D 1

33 C 1

34 C 1

35 D 1

36 A 1

37 C 1

38 D 1

39 B 1

40 D 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1 D 1

2 D 1

3 B 1

4 C 1

5 C 1

6 C 1

7 C 1

8 A 1

9 B 1

10 B 1

11 D 1

12 C 1

13 D 1

14 B 1

15 A 1

16 C 1

17 D 1

18 A 1

19 D 1

20 D 1

21 C 1

22 A 1

23 D 1

24 D 1

25 A 1

26 B 1

27 D 1

28 C 1


May/June 2017



29 A 1

30 C 1

31 B 1

32 B 1

33 C 1

34 C 1

35 B 1

36 B 1

37 C 1

38 D 1

39 B 1

40 B 1






CHEMISTRY 0620/31 Paper 3 Theory (Core) May/June 2017

MARK SCHEME

Maximum Mark: 80

Published

This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the May/June 2017 series for most Cambridge IGCSE®, Cambridge International A and AS Level and Cambridge Pre-U components, and some Cambridge O Level components.


May/June 2017



1(a)(i) A 1

1(a)(ii) E 1

1(a)(iii) C 1

1(a)(iv) B 1

1(a)(v) C 1

1(b) number of electrons in Br – = 36 1

number of neutrons in Cl = 18 1

number of protons in Cl = 17 AND number of protons in Br – = 35 1


2(a)(i) Na+ / sodium 1

2(a)(ii) sulfite / sulfate(IV) 1

2(a)(iii) 3 (mg) 1

2(a)(iv) 36.3 (mg) 1

2(a)(v) calcium hydrogencarbonate 1

2(b) flame test 1

yellow 1

2(c) MgCl2 1


May/June 2017



2(d) negative electrode: calcium / Ca 1

positive electrode: chlorine / Cl2 1


3(a) any 5 of: X has covalent bonding X particles are randomly arranged / irregularly arranged X particles are moving rapidly / freely / randomly / irregularly Y has ionic bonding / ionic Y particles are regularly arranged / lattice / in rows / uniformly arranged Y particles (only) vibrate / do not move from place to place Z has covalent bonding Z particles are regularly arranged / lattice / in a tetrahedral shape Z particles (only) vibrate / do not move from place to place

5

3(b) volume gets smaller 1

particles get closer together 1

3(c) drill tips / drills / cutting (tools) 1

3(d) A / substance Y dissolves easily in water 1

C / substance Y melts (at 8015 °C) 1

the change can be reversed by altering the conditions 1


May/June 2017



4(a) has two atoms in a molecule / two atoms combined 1

4(b)(i) the chlorine has displaced / replaced the bromine (in KBr) 1

4(b)(ii) (from green / colourless) to orange 1

4(b)(iii) I2 1

KBr 1

4(c) add (nitric acid then aqueous) silver nitrate 1

yellow precipitate 1

4(d)(i) water purification / water treatment / killing bacteria / in (swimming) pools / disinfectant 1

4(d)(ii) breaking down of a compound / breaking down of a substance 1

(using) heat 1

4(d)(iii) any 2 distinct pollution problems: • litter OR eyesore • sticks in gullets OR throats of birds / animals • blocking of drains OR watercourses • animals gets trapped OR tangled (in plastic) • poisonous vapours when burned • fills landfill sites

2


May/June 2017



5(a) circle drawn around the OH group 1

5(b) 20 1

5(c) C=C double bond 1

5(d)(i) increases with an increasing number of carbon atoms ORA 1

5(d)(ii) any value between –88 and 0 (°C) (exclusive of these values) 1

5(d)(iii) there is no (clear) trend / the numbers go down and up 1

5(d)(iv) liquid 1

30 °C is between melting and boiling point / 30 °C is above the melting point and below the boiling point 1

5(d)(v) substance containing carbon and hydrogen 1

only / and no other element 1

5(d)(vi)

1

5(d)(vii) 3 (CO2) 1

5 (O2) 1

C C

H H

H H

H H


May/June 2017



6(a)(i) aluminium

low density 1

good electrical conductivity 1

6(a)(ii) iron is cheap(er) / tungsten is (too) expensive OR iron is strong(er) / tungsten is weaker

1

6(a)(iii) tungsten because it has a (very) high melting point 1

6(b) any 2 properties: • high melting point / high boiling point • high density • hard / strong • sonorous / rings (when hit) • ions are coloured / compounds are coloured

2

6(c) 2 (W) 1

3 (O2) 1

6(d) tungsten < cobalt < iron < magnesium IF full credit is not awarded, allow 1 mark for either a correct sequence apart from a consecutive pair reversed OR for the whole sequence reversed

2

6(e)(i) the more concentrated the acid, the greater the rate ORA 1

6(e)(ii) nitric (acid) 1

6(e)(iii) any value between 19 and 39 hours (exclusive of these values) 1

6(e)(iv) pH 4 1


May/June 2017



7(a) the energy of the reactants is greater than the energy of the products / the product has less energy than the reactants / the arrow is going down (from reactants to product)

1

7(b) any 2 sources: • carbon monoxide from incomplete combustion of fossil fuels / named fossil fuel / named carbon-containing fuel • carbon dioxide from combustion of fossil fuels / respiration • methane from animal flatulence / rice paddy fields / bacteria / decomposition of vegetation / decomposition of

animals any 3 effects:

• carbon dioxide: global warming / greenhouse effect / acidification of oceans • methane: global warming / greenhouse effect • carbon monoxide: poisonous / toxic

5

7(c)(i) making mortar / whitewash / neutralising (acidic) soils / neutralising acidic lakes / flue gas desulfurisation / steelmaking / glassmaking / making plaster

1

7(c)(ii) 100 IF full credit is not awarded, allow 1 mark for (Ca =) 40, (C =) 12 and (O =) 16

2

7(d) add hydrochloric acid to the mixture 1

filter off the carbon 1

wash carbon (with water or other solvent) AND dry in an oven / air dry / leave in air / leave to dry 1






CHEMISTRY 0620/32 Paper Theory (Core) May/June 2017

MARK SCHEME

Maximum Mark: 80

Published



May/June 2017



1(a)(i) A 1

1(a)(ii) B 1

1(a)(iii) B 1

1(a)(iv) E 1

1(a)(v) C 1

1(b) number of electrons in O2– ion = 10 1

number of neutrons in S = 18 1

number of protons in S = 16 AND in O2– ion = 8 1


May/June 2017



2(a)(i) chloride 1

2(a)(ii) sodium / Na+ 1

2(a)(iii) 0.4 (mg) 1

2(a)(iv) 34 (mg) 1

2(a)(v) sodium hydrogencarbonate 1

2(b) flame test 1

lilac colour 1

2(c) KNO3 1

2(d) negative electrode: potassium / K 1

positive electrode: bromine / Br 1


May/June 2017



3(a) any 5 of: X has ionic bonding / ionic X particles are regularly arranged / lattice / in rows / uniformly arranged X particles (only) vibrate / do not move from place to place Y has covalent bonding Y has irregular arrangement of particles / random arrangement Y particles are sliding over each other / moving slowly Z has covalent bonding Z particles are randomly arranged / irregularly arranged Z particles moving randomly / moving rapidly / moving freely / moving quickly / moving fast

5

3(b) volume increases / volume gets larger 1

particles get further apart 1

3(c) white 1

to blue 1

3(d) it has (two different types of) atoms bonded / joined 1


May/June 2017



4(a)(i) bauxite 1

4(a)(ii) it is (very) reactive / too reactive / above carbon in the reactivity series / more reactive than carbon 1

4(b)(i) hydrogen/ H2 1

4(b)(ii) gas syringe connected to a flask OR this described in words 1

closed apparatus / workable apparatus OR this described in words 1

timer or stopwatch OR this described in words 1

4(c) for aircraft / car bodies 1

low density 1

4(d) any 2 advantages: • saves energy • saves mining of ore • saves other finite resources • saves transport costs of bringing ore to factory • reduces pollution(due to dust or exhaust fumes etc.)

2

4(e)(i) (zinc oxide) loses oxygen 1

4(e)(ii) reactant level below product level / reactants have less energy than products / products have more energy than reactants 1


May/June 2017



5(a)(i) circle around carboxylic acid group 1

5(a)(ii) alcohol 1

5(b) C3H6O3 1

5(c) alcohol group shown as O–H 1

rest of the structure correct 1

5(d)(i) how easily it evaporates / boils 1

5(d)(ii) butanol 1

5(d)(iii) any value between 65 and 98 (°C) (exclusive of these values) 1

5(d)(iv) gas / vapour 1

120°C is above the boiling point 1

5(e)(i) 2 (H2O) 1

O2 1

5(e)(ii) 32 IF full credit is not awarded, allow 1 mark for (C =) 12, (O =) 16 and (H =) 1

2


May/June 2017



6(a) M

(good) resistance to corrosion 1

high(est) relative strength 1

6(b) Q 1

6(c) any 3 from: • high melting point / high boiling point • high density • forms coloured compounds / compounds are coloured / ions are coloured • has more than one oxidation state / forms ions with different charges • forms complex ions • catalyst • hard / strong • sonorous / rings (when hit)

3

6(d) 2 (HCl ) 1

H2 1

6(e) gold < copper < iron < potassium IF full credit is not awarded, allow 1 mark for either a correct sequence apart from a consecutive pair reversed OR for the whole sequence reversed

2

6(f)(i) the higher the concentration the faster the rate / the lower the concentration the slower the rate / as the concentration increases the rate of reaction increases

1

6(f)(ii) phosphoric 1

6(f)(iii) any value between 45 and 102 hours (exclusive of these values) 1

6(f)(iv) pH 2 1


May/June 2017



7(a) (substance containing) only one type of atom 1

7(b) underground / volcanoes / crude oil / petroleum 1

suitable use, e.g. (making) sulfuric acid / making SO2 / dusting plants / vulcanising rubber 1

7(c) sublimation / subliming / sublime 1

7(d) any 2 sources: • sulfur dioxide: from volcanoes / burning fossil fuels • oxides of nitrogen: from car exhausts / high temperature furnaces / lightning

any 3 effects:

• sulfur dioxide: acid rain / named effects of acid rain • sulfur dioxide: irritates eyes or skin • oxides of nitrogen: acid rain / named effect of acid rain • oxides of nitrogen: breathing difficulties / breathing problems / irritates eyes / skin / photochemical smog

5

7(e) add hydrochloric acid to the mixture 1

filter off the sulfur / sulfur on filter paper 1

wash sulfur (with water or other solvent) AND dry in an oven / air dry / leave to dry (in air) 1






CHEMISTRY 0620/33 Paper 3 Theory (Core) May/June 2017

MARK SCHEME

Maximum Mark: 80

Published



May/June 2017



1(a)(i) E 1

1(a)(ii) C 1

1(a)(iii) C 1

1(a)(iv) D 1

1(a)(v) A 1

1(b) number of electrons in Ca2+ = 18 1

number of neutrons in Mg = 14 1

number of protons in Mg = 12 AND number of protons in Ca2+ = 20 1


May/June 2017



2(a)(i) 8 (mg) 1

2(a)(ii) hydrogencarbonate / HCO3– 1

2(a)(iii) nitrate 1

2(a)(iv) 12.5 (mg) 1

2(b) (damp) red litmus paper 1

turns blue 1

2(c) CaBr2 1

2(d)(i) negative electrode: calcium / Ca 1

positive electrode: bromine / Br2 1

2(d)(ii) platinum / Pt 1


May/June 2017



3(a) any 5 of: P has ionic bonding / ionic P particles are regularly arranged / lattice / in rows / uniformly arranged P particles (only) vibrating / not moving from place to place Q has covalent bonding Q has irregular arrangement of particles / random arrangement Q particles moving slowly / moving randomly / sliding over each other R no bonding (between atoms) / weak bonding between atoms / weak attractive forces between atoms R has irregular arrangement of particles / random arrangement R particles moving randomly / moving rapidly / freely moving / randomly (moving) / irregular (movement)

5

3(b) volume increases 1

particles get further apart 1

3(c) C / boils (at 1330 °C) 1

D / dissolves (readily in water) 1

the change can be reversed by altering the conditions 1

3(d) pencil (leads) / lubricant 1

layers move OR slide over each other 1


May/June 2017



4(a)(i) hematite / any other ore of iron 1

4(a)(ii) from the reaction of carbon dioxide 1

with carbon / coke 1

OR

reaction of carbon / coke 1

with insufficient oxygen for compete combustion / idea of oxygen not in excess or not limiting 1

4(a)(iii) 2 (Fe) 1

3 (CO2) 1

4(a)(iv) iron(III) oxide loses oxygen / iron(III) oxide loses oxygen 1

4(a)(v) 160 IF full credit is not awarded, allow 1 mark for (Fe =) 56 and (O =16)

2

4(b)(i) hydrogen / H2 1

4(b)(ii) gas syringe connected to flask OR this described in words 1

closed apparatus / workable apparatus OR this described in words 1

timer / stop-watch OR this described in words 1

4(c) (aqueous) sodium hydroxide / aqueous ammonia 1

green precipitate 1

4(d) any 2 advantages from: saves energy / saves mining of ore / saves other finite resources / saves transport costs of bringing ore to factory / reduces dust pollution / exhaust gas pollution

2


May/June 2017



5(a) circle drawn around the COOH group 1

5(b) C2H4O3 1

5(c) grind up the (sugar) cane / crush the plant 1

with a solvent 1

filter (off the solution) 1

5(d) addition of oxygen / loss of electrons / increase in oxidation number 1

5(e)(i) decreases with an increasing number of carbon atoms ORA 1

5(e)(ii) any value between 118 and 164 (°C) (exclusive of these values) 1

5(e)(iii) solid 1

–10 (°C) is below the melting point / melting point is higher than –10 (°C) 1


May/June 2017



6(a)(i) J

it is (very) strong / it is the strongest 1

it is cheap 1

6(a)(ii) M because it is the hardest 1

6(a)(iii) K because its density is the lowest 1

6(b)(i) line at a steeper gradient than W 1

ends up at same mass loss 1

6(b)(ii) Y 1

6(b)(iii) 1.05 days 1

6(b)(iv) increasing temperature increases rate 1

increasing concentration increases rate 1

6(c) pH 12 1


May/June 2017



7(a) pair of electrons in overlap area between O atom and both H atoms 1

7(b) electrical conductivity 1

melting point / boiling point 1

7(c) iron < magnesium < cerium < lithium IF full credit is not awarded, allow 1 mark for either a correct sequence apart from a consecutive pair reversed OR for the whole sequence reversed

2

7(d)(i) water 1

air / oxygen 1

7(d)(ii) any 2 methods from: greasing / covering with plastic / galvanising / painting / (electro)plating

2

7(e) evaporate to crystallisation point / leave in a warm place until crystals form 1

filter off crystals / pick out crystals AND dry on filter paper / heat in drying oven 1

7(f) 4 (CO2) 1

4(H2O) 1






CHEMISTRY 0620/41 Paper 4 Theory Extended May/June 2017

MARK SCHEME

Maximum Mark: 80

Published



May/June 2017



1(a) proton number: the number of protons 1

nucleon number: the total number of protons and neutrons 1

nucleon number: in the nucleus / nuclei (of an atom) 1

1(b) (hydrogen is the only atom to have) no neutrons 1

1(c)

number of protons

number ofneutrons

number ofelectrons

19F 9 10 9 26Mg 12 14 12 31P3– 15 16 18 87Sr2+ 38 49 36

fluorine protons AND neutrons correct 1

magnesium neutrons AND electrons correct 1

phosphorus protons AND neutrons correct 1

phosphorus electrons correct 1

strontium protons AND neutrons correct 1

strontium electrons correct 1

1(d)(i) MgF2 1

1(d)(ii) Sr3P2 1


May/June 2017



2(a)(i) SO2 1

2(a)(ii) Na2O 1

2(a)(iii) Cr2O3 1

2(a)(iv) SiO2 1

2(a)(v) Al2O3 / Cr2O3 1

2(a)(vi) CO 1

2(b)(i) an amphoteric oxide will react with acids AND with bases 1

2(b)(ii) a neutral oxide will not react with acids or with bases 1


3(a)(i) no (more) effervescence 1

3(a)(ii) magnesium carbonate 1

3(a)(iii) (a solution in which) no more solute will dissolve 1

at that temperature 1

3(a)(iv) the solubility deceases as the temperature decreases 1

3(b)(i) moles of water = 2.52 / 18 = 0.14 (mol) 1

3(b)(ii) moles of anhydrous magnesium sulfate = 0.02 (mol) 1

3(b)(iii) ratio = 0.02 / 0.02 : 0.14 / 0.02 = 1 : 7 1


May/June 2017



3(b)(iv) MgSO4.7H2O M1 MgSO4 M2 rest of the formula correct

2

3(c) mix and stir the two solutions 1

filter (to obtain residue) 1

wash (the residue) using water 1

dry the residue between filter papers / in a warm place 1

3(d) Pb2+(aq) + SO42–(aq) → PbSO4(s)

M1 correct species M2 correct state symbols

2


4(a)(i) roast in air 1

4(a)(ii) 2ZnS + 3O2 → 2ZnO + 2SO2 M1 correct species M2 correct balancing

2

4(b)(i) coke 1

4(b)(ii) zinc is vaporised / boiled 1

and is condensed 1


May/June 2017



4(c)(i) Zn → Zn2+ + 2e– M1 correct species M2 correct balancing

2

4(c)(ii) 2H+ + 2e– → H2 M1 correct species M2 correct balancing

2

4(c)(iii) change: (the intensity would) decrease 1

reason: the difference in reactivity between zinc and iron is less than the difference in reactivity between zinc and copper 1


5(a) (stop-) watch AND syringe 1

5(b) graph starts at X and is a curve with a decreasing gradient 1

graph hits zero rate at 114 ± 6 seconds 1

5(c) M1 moles of carbon dioxide = 180 / 24 000 = 0.0075 1

M2 molar mass of barium carbonate = 197 1

M3 mass of barium carbonate = M1 × M2 = 1.48 (g) 1

5(d) curve starts from (0,0) and has a lower gradient than the original curve 1

because lumps have a lower surface area 1


May/June 2017



5(e) curve starts from (0,0) and has a steeper gradient than the original curve 1

finishes at the same volume of gas 1

because there are more particles per unit volume / dm3 / cm3 1

because there are more collisions per second / unit time OR a greater collision rate 1

5(f) 360 (cm3) 1


6(a) (compound that) contains carbon and hydrogen 1

and no other elements / only 1

6(b) any 3 from: • same / similar chemical properties • (same) general formula • (consecutive members) differ by CH2 • same functional group • common (allow similar) methods of preparation • physical properties vary in predictable manner / show trends / gradually change / example of a physical property

variation

3

6(c) propene 1

structure correctly shown 1

6(d) steam 1

catalyst 1


May/June 2017



6(e)(i) butanoic acid 1

1

6(e)(ii) acidified 1

(potassium) manganate(VII) 1

6(e)(iii) oxidation 1

6(f) methanol 1

ethanoic acid 1

catalyst 1

heat 1

CH3COOH + CH3OH → CH3COOCH3 + H2O 1






CHEMISTRY 0620/42 Paper 4 Theory (Extended) May/June 2017

MARK SCHEME

Maximum Mark: 80

Published



May/June 2017



1(a)(i) fractional distillation 1

1(a)(ii) chromatography 1

1(a)(iii) fermentation / ferment 1

1(a)(iv) (simple) distillation / distil 1

1(a)(v) filtration / decantation / centrifugation 1

1(b)(i) (substance that) cannot be split up / broken down into (two or more) simpler substances by chemical means OR (substance) made of atoms with the same atomic number / number of protons / proton number

1

1(b)(ii) (two or more) elements joined or combined or bonded (together) 1

1(b)(iii) (particle) containing different numbers of protons and electrons OR atom or group of atoms that has gained or lost an electron / electrons

1


May/June 2017



2(a) atoms of the same element / atoms with the same proton number / atoms with the same atomic number 1

different neutron number / different nucleon number / different mass number 1

2(b)

carbon silicon

proton number 6 14 M1 electronic structure 2,4 2,8,4 M2

nucleon number 12 28

number of neutrons in one atom 6 14 M3

3

2(c)(i) covalent 1

2(c)(ii) award 1 mark for each correct property and one mark for each correct matching reason. 4

property: high melting point / high boiling point reason: bonds between atoms are strong OR covalent bonds are strong / bonds need large amount of energy to break

property: non-conductor / poor conductor(of electricity) / insulator reason: no moving charged particles / no moving ions / no moving electrons / all (outer shell) electrons used in bonding

property: hard reason: bonds between atoms are strong OR covalent bonds are strong

property: brittle reason: bonds between atoms are strong OR covalent bonds are strong / bonds are directional

property: insoluble reason: does not form hydrogen bonds with water / no ions that can be hydrated

2(d)(i) incomplete combustion / incomplete burning / combustion in insufficient air / oxygen 1

of fossil fuels / named fossil fuel / named petroleum fraction / name or formula of a type of substance containing carbon 1

2(d)(ii) toxic / poisonous / combines with or binds to haemoglobin 1


May/June 2017



2(e)(i) carbon dioxide: (simple) molecular / simple covalent 1

silicon(IV) dioxide: macromolecular / giant molecular / giant covalent / giant atomic 1

2(e)(ii) carbon dioxide: weak (force of) attraction between molecules / weak intermolecular forces / weak van der Waals’ forces / weak dispersion forces / weak London forces

1

silicon(IV) dioxide: covalent bonds are strong / force of attraction between atoms is strong / no weak bonds (are present) / all bonds are strong

1

(weak) forces of attraction in carbon dioxide need small amounts of energy or heat to break / less energy or heat needed to break forces of attraction in carbon dioxide OR (strong) bonds in silicon(IV) dioxide need large amounts of energy or heat to break / more energy or heat needed to break bonds in silicon(IV) dioxide

1

2(f) 2NaOH + SiO2 → Na2SiO3 + H2O IF full credit is not awarded, allow 1 mark for Na2SiO3 OR 2OH– + SiO2 → SiO3

2– + H2O M1 species correct M2 balancing

2


May/June 2017



3(a)(i) 450 °C 1

200 atmospheres 1

3(a)(ii) iron 1

3(b)(i) 4(NO) 1

5(O2) AND 6(H2O) 1

3(b)(ii) lower yield of NO / lower yield of nitric acid / lower yield of product / equilibrium shifts to left (at higher temperatures) / backward reaction favoured(at higher temperatures) ORA

1

3(b)(iii) too slow / rate decreases ORA 1

3(c) 4NO + 3O2 + 2H2O → 4HNO3 M1 all formulae correct M2 balancing

2

3(d) add copper(II) carbonate (to acid) until it stops dissolving or no more effervescence / bubbling / fizzing 1

filter (to remove copper(II) carbonate) 1

evaporate / heat / warm / boil / leave in sun AND until most of the water has gone / some water is left / evaporate some of the water / until it is concentrated / saturation (point) / crystallisation point / crystals form on glass rod or microscope slide / crystals start to form

1

(for any solution) leave / allow to cool / allow to crystallise OR (for any crystals) filter / wash / dry with filter paper / dry in warm place / dry in a (low) oven / leave to dry

1

formula of Cu(NO3)2 1

equation: CuCO3 + 2HNO3 → Cu(NO3)2 + CO2 + H2O 1


May/June 2017



4(a) any 3 from: • catalyst • more than one / variable oxidation state / oxidation number / valency • form coloured compounds / coloured ions • forms complex ions / complexes

3

4(b) add sodium hydroxide (solution) / NaOH / potassium hydroxide (solution) / KOH 1

zinc oxide dissolves / reacts OR copper(II) oxide does not dissolve / react 1

filter / decant / centrifuge (copper(II) oxide) 1

4(c)(i) Zn → Zn2+ + 2e / 2e– M1 formula of Zn2+ on the right-hand side M2 equation fully correct

2

4(c)(ii) zinc / Zn nickel / Ni copper / Cu

1

4(c)(iii) copper (+) and nickel (–) 1

0.59 V 1


May/June 2017



5(a)(i)

5 cells completed correctly = [3] 3 or 4 cells completed correctly = [2] 2 cells completed correctly = [1]

aqueous potassium chloride

aqueous potassium bromide

aqueous potassium iodide

chlorine bromine iodine

3

5(a)(ii) Cl2 + 2KBr → 2KCl + Br2 OR Cl2 + 2Br

– → 2Cl – + Br2

1

5(b)(i) white 1

5(b)(ii) 0.02 (mol) 1

5(b)(iii) 0.02 (mol) 1

5(b)(iv) 1:2 1

VCl2 1


May/June 2017



5(c)(i) solid 1

5(c)(ii) 2Na + At2 → 2NaAt M1 formula of NaAt M2 equation fully correct

2

5(d)(i) 393 (kJ) 1

5(d)(ii) 416 (kJ) 1

5(d)(iii) –23 (kJ / mol) 1


6(a)(i) alkene 1

carboxylic acid 1

6(a)(ii) any 2 from: • same / similar chemical properties • (same) general formula • (consecutive members) differ by CH2 • same functional group • common (allow similar) methods of preparation • physical properties vary in predictable manner / show trends / gradually change / example of a physical property

variation

2

6(b) carboxylic acid / aldehyde 1

ester 1

6(c)(i) colourless / decolourised 1

bubbles / fizzing / effervescence 1


May/June 2017



6(c)(ii) addition 1

repeat unit

1

continuation bonds at both ends 1






CHEMISTRY 0620/43 Paper 4 Theory (Extended) May/June 2017

MARK SCHEME

Maximum Mark: 80

Published



May/June 2017



1(a)(i) J 1

1(a)(ii) E 1

1(a)(iii) D 1

1(a)(iv) J 1

1(a)(v) L 1

1(a)(vi) D 1

1(b)(i) (atoms with) same number of protons / atomic number / of same element 1

different number of neutrons / different mass number / different nucleon number 1

1(b)(ii) E AND G 1

1(b)(iii) they have the same number of electrons in their outer shell 1


May/June 2017



2(a)(i) CH2 1

2(a)(ii) initial colour: orange 1

final colour: colourless / none 1

2(b)(i) approximately horizontal line draw to right of and below the reagent line 1

energy change shown starting level with the reactant energy AND finishing level with the product energy AND having only one (correct) arrow head AND labelled ∆H / energy change

1

2(b)(ii) (energy required to break bonds =) 3624 1

(energy given out when bonds made =) 3738 1

–114 (kJ / mol) 1

2(c) (attractive) forces between molecules 1

(forces of attraction) are stronger in iodine 1


May/June 2017



3(a) regular arrangement / lattice of positive ions / magnesium ions / Mg2+ ions 1

sea of electrons OR delocalised electrons 1

attraction between (positive) ions and (delocalised / sea of) electrons 1

3(b) electrons 1

move / flow (throughout / through the structure) 1

3(c) layers (of atoms or ions) 1

layers / atoms / ions can slide / slip / glide (over each other) (without breaking the metallic bonds) 1

3(d)(i) magnesium shown as (2, 8) using crosses 1

sulfide shown as (2, 8, 8), with the two gained electrons in the outer shell of sulfur shown as crosses and all other electrons on sulfur shown as dots

1

magnesium ion charge as 2+ AND sulfide charge as 2– 1

3(d)(ii) melt / fused 1

ions can move OR are mobile 1


May/June 2017



4(a) petroleum 1

4(b)(i) saturated: only single bonds OR no double / multiple bonds (between carbon atoms) 1

hydrocarbon: (compound that) contains carbon and hydrogen 1

hydrocarbon: and no other elements / only 1

4(b)(ii) alkane(s) 1

4(b)(iii) any 2 from: • same / similar chemical properties • (same) general formula • (consecutive members) differ by CH2 • same functional group • common (allow similar) methods of preparation • physical properties vary in predictable manner / show trends / gradually change / example of a physical

property variation

2

4(b)(iv) CO2 and H2O on right-hand side and no other products / reagents 1

11 (O2), 7 (CO2), 8 (H2O) 1

4(c)(i) acid rain 1


May/June 2017



4(c)(ii) carbon monoxide: from incomplete combustion (of fuel) 1

oxides of nitrogen: nitrogen (from the air) reacts with oxygen (from the air) 1

oxides of nitrogen: at high temperatures (in engine) OR (electrical) spark (in the engine) 1

4(c)(iii) poisonous / toxic / death 1

4(c)(iv) any 3 from: • oxides of nitrogen are reduced / lose oxygen (to form nitrogen) • oxides of nitrogen form nitrogen • (oxides of nitrogen) react with carbon monoxide • gases (adsorb / stick) on the catalyst’s surface

3

4(d)(i) butane 1

4(d)(ii) (molecules with) the same molecular formula 1

different structural formula / different displayed formula 1

4(d)(iii) UV light / sunlight 1

H–Cl 1

any mono to deca chloro-substituted derivative of methyl propane 1


May/June 2017



5(a)(i) loss (of electrons) 1

5(a)(ii) Ni → Ni2+ + 2e– 1

5(a)(iii) goes down / gets less / decreases / lower / smaller 1

5(b)(i) beryllium 1

most negative voltage with any (named) metal OR biggest voltage with cobalt / nickel 1

5(b)(ii) cobalt AND nickel 1

5(b)(iii) – sign 1

2.7 1

5(c) (set up cell) using magnesium and beryllium (electrodes) 1

voltage positive if magnesium is metal 2 1

OR

(set up cells) using both magnesium and beryllium with the same metal as the other electrode 1

larger (magnitude) voltages with magnesium 1

OR

use magnesium with a different metal and compare to a reference value in a table 1

value is more negative than with beryllium, if magnesium is metal 1 1


May/June 2017



6(a)(i) BaCO3 → BaO + CO2 1

6(a)(ii) anything pH in the range pH 10 to pH 14 1

6(a)(iii) nitrogen dioxide 1

oxygen 1

6(b)(i) Na2CO3 + Ba(NO3)2 → BaCO3 + 2NaNO3 M1 formula of NaNO3 M2 equation fully correct

2

6(b)(ii) filter 1

wash (the residue) using water 1

dry the residue between filter papers / in a warm place 1

6(c)(i) Mr = 197 1

(9.85 / 197 =) 0.05 (mol) 1

6(c)(ii) 0.05 (mol) 1

6(c)(iii) (0.05 × 24) = 1.2 (dm3) 1

6(c)(iv) moles of HCl at the start = (250 / 1000 × 1.00) = 0.25 1

moles HCl in excess = 0.25 – (2 × 0.05) = 0.15 (mol) 1






CHEMISTRY 0620/51 Paper 5 Practical Test May/June 2017

MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(b) initial and final readings completed correctly 1

differences completed correctly 1

all readings to 1 d.p. 1

results comparable to the Supervisor’s results 1

1(c) red / brown / amber / orange 1

1(d) (becomes) yellow / orange / paler 1

1(e) yellow to blue / black 1

1(f)(i) solution C is more concentrated 1

a greater volume of thiosulfate was needed 1

1(f)(ii) ratio of the candidate’s differences from the table in (b) 1

1(g) 1.5 × value from table in (b) for Experiment 2 1

unit: cm3 1

1(h)(i) 2 sources of error, e.g.: • using a measuring cylinder to measure solution C / solution D • only carrying out the experiments once • going past the end-point

2

1(h)(ii) 2 meaningful improvements related to (h)(i): • use a pipette / burette • repeat the experiment • improvement linked to going past the end-point

2


May/June 2017



2(a) green 1

2(b) any 2 from: • turns black • condensation / drops of liquid formed • moves / jumps around

2

2(c)(i) any 3 from: • blue (solution) • bubbles / fizz • limewater • milky

3

2(c)(ii) blue 1

precipitate 1

(with excess) deep / royal blue solution / clear / precipitate dissolves 1

2(d) blue-green 1


May/June 2017



2(e) copper / Cu2+ 1

carbonate / CO32– 1

2(f) white 1

2(g)(i) no reaction / no change 1

2(g)(ii) yellow precipitate 1

2(h) lilac 1

2(i) potassium / K+ 1

iodide / I– 1


3(a) (red) litmus turns blue 1

3(b)(i) heat / boil the mixture 1

condense the vapour 1

3(b)(ii) filter / decant 1

wash residue (with water) 1

dry 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(a) initial volume, final volume and difference completed correctly 1

difference comparable to the Supervisor’s result 1

1(b) initial volume, final volume and difference completed correctly 1

all readings in both tables in (a) and (b) to 1 d.p. 1

1(c)(i) pink / purple / violet to colourless / pale green 1

1(c)(ii) there is a colour change at the end-point already 1

1(d)(i) solution C 1

a greater volume of potassium manganate(VII) / solution A was needed 1

1(d)(ii) ratio of the candidate’s differences from the tables in (a) and (b) 1

1(e)(i) 2 × value from the table in (b) 1

double the volume of solution C was used / double the volume of solution A was needed 1

1(e)(ii) problem: volume of potassium manganate(VII) solution added would be greater than 50 cm3 1

solution: use more than one burette / refill burette 1

1(f) advantage: easy (to use) / quick 1

disadvantage: not accurate 1


May/June 2017



2(a) yellow 1

2(b) initial and final temperatures recorded 1

temperature difference correctly calculated 1

2(c) any 3 from: • (pale) yellow • precipitate • potassium manganate(VII) turns colourless

3

2(d) no reaction / no change 1

2(e)(i) any 2 from: • brown • turns blue-black • white precipitate

2

2(e)(ii) blue-black colour disappears / turns colourless 1

white 1

2(f) sodium / Na+ 1

sulfite / SO32– 1

2(g) red 1

2(h) white 1

precipitate 1

2(i) no reaction / no change 1


May/June 2017



2(j) lithium / Li+ 1

chloride / Cl – 1


May/June 2017



3 6

the filtration method any 6 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • filter • wash residue / kaolinite • dry • weigh residue / kaolinite • (change in mass / initial mass) × 100 (%)

the gas collection / loss of mass method any 6 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • collect gas in a syringe / measure final total mass • measure volume of gas / mass loss • calculate moles of CaCO3 / CO2 • calculate mass of CaCO3 • (mass of CaCO3 / initial mass) × 100 (%)

the calcium chloride method any 4 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • filter







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(a) volume at time = 0 s completed correctly 1

all volumes completed and in ascending order 1

1(b) volume at time = 0 s completed correctly AND all volumes completed and in ascending order 1

gas volumes increase less quickly at the start of Experiment 2 than at the start of Experiment 1 1

1(c) all points correctly plotted 2

two smooth lines 1

labelled 1

1(d) Experiment 1 1

more concentrated / stronger acid / the acid has a lower pH 1

1(e) volume of gas at 30 s 1

correct calculation of rate 1

unit: cm3 / s OR cm 3

s–1 1

1(f) all the magnesium will have reacted 1

1(g) faster reaction / increased rate 1

magnesium powder has a higher surface area 1


May/June 2017



1(h) advantage: easy to use / quick 1


1(i) use of burette / pipette / gas syringe / weighed amount of magnesium / repeat experiment (and average) / clean the magnesium / remove oxide layer

1


2(a) black (powder) 1

2(b)(i) bleached / white / decolourised 1

2(b)(ii) brown 1

precipitate 1

2(c) chlorine 1

2(d) any 3 from: • turns yellow • bubbles / fizz • red / brown / orange • precipitate

3

2(e) yellow / brown 1

blue / black 1

2(f) turns colourless 1


May/June 2017



2(g) fizz / bubbles 1

glowing splint 1

relights 1

2(h) oxygen 1


3 any 6 from: • crush lumps • pestle and mortar • weigh cassiterite • heat / reduce • with carbon / CO / more reactive metal, e.g. Zn • weigh tin • (mass of tin / initial mass) × 100 (%)

6






CHEMISTRY 0620/61 Paper 6 Alternative to Practical May/June 2017

MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(a)(i) stirrer / glass rod 1

1(a)(ii) Spatula 1

1(a)(iii) nitric (acid) 1

1(a)(iv) bubbles / fizz / effervescence 1

1(b) the reaction is (fast) at room temperature 1

1(c) strontium carbonate 1

solid is left behind 1

1(d) filter 1

heat / evaporate 1

to crystallising point / glass rod test / until saturation point 1


2(a) initial and final readings completed correctly: 4.1, 38.3 1

difference completed correctly: 34.2 1

2(b) initial and final readings completed correctly: 3.7, 20.8 1

difference completed correctly: 17.1 1

2(c)(i) solution C is more concentrated 1

a greater volume of thiosulfate was needed 1

2(c)(ii) 2 × as concentrated 1


May/June 2017



2(d) 1.5 × value from table in (b) for Experiment 2 1

unit: cm3 1

2(e)(i) 2 sources of error, e.g.: • using a measuring cylinder to measure solution C / solution D • only carrying out the experiments once • going past the end-point

2

2(e)(ii) 2 meaningful improvements related to (e)(i): • use a pipette / burette • repeat the experiment • improvement linked to going past the end-point

2


3(a) solid spits out of the tube / the tube might crack 1

3(b) carbon dioxide 1

3(c) copper / Cu2+ 1

carbonate / CO32– 1

3(d) white 1

3(e)(i) no reaction / change 1

3(e)(ii) yellow 1

precipitate 1

3(f) lilac 1


May/June 2017



3(g) any 2 from: • blue / roaring / hot flame • use of a splint / wire to introduce the solid into the flame • use of (concentrated) hydrochloric acid

2


4(a) (red) litmus turns blue 1

4(b) heat / boil the mixture 1

condense the vapour 1

4(c) filter / decant 1

wash residue (with water) 1

dry 1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(a) measuring cylinder 1

conical flask 1

1(b) bubbles / fizz / effervescence 1

1(c) time (taken) 1

s / seconds / secs 1

1(d)(i) 80 and 40 (cm3) 1

Experiment 1 at twice / double the volume of Experiment 2 1

1(d)(ii) two times as much / mass / amount / length magnesium used (in Experiment 1) 1

1(d)(iii) curve drawn is steeper than Experiment1 1

curve drawn finishes at the same level as Experiment 1 1


2(a) initial volume completed correctly: 0.0 final volume completed correctly: 13.0

1

difference: 13.0 1

2(b) final volume, initial volume and difference completed correctly: 41.1, 2.1 and 39.0 1

all readings in (a) and (b) to 1 d.p. 1

2(c) there is a colour change at the end-point already 1

2(d)(i) solution C 1

a greater volume of potassium manganate(VII) / solution A was needed 1


May/June 2017



2(d)(ii) 3 × as concentrated 1

2(e)(i) double the volume of solution C was used / double the volume of solution A was needed 1

78 cm3 1

2(e)(ii) problem: volume of potassium manganate(VII) solution added would be greater than 50 cm3 1

solution: use more than one burette / refill burette 1

2(f) advantage: easy (to use) / quick 1


2(g) can take average or mean / can spot anomalies / more reliable 1


3(a) initial temperature and final temperature recorded correctly: 19, 23 1

temperature difference correctly calculated: 4 1

3(b) endothermic 1

3(c) sulfur dioxide 1

3(d) sodium / Na+ 1

sulfite / SO32– 1

3(e) red 1

3(f) white 1

precipitate 1


May/June 2017



4 6

the filtration method any 6 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • filter • wash residue / kaolinite • dry • weigh residue / kaolinite • (change in mass / initial mass) × 100 (%)

the gas collection / loss of mass method any 6 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • collect gas in a syringe / measure final total mass • measure volume of gas / mass loss • calculate moles of CaCO3 / CO2 • calculate mass of CaCO3 • (mass of CaCO3 / initial mass) × 100 (%)

the calcium chloride method any 4 from:

• weigh mixture (of calcium carbonate and kaolinite) • add (dilute) hydrochloric acid • in excess / continue adding until there is no more fizzing / add until no more gas is evolved • filter

1







MARK SCHEME

Maximum Mark: 40

Published



May/June 2017



1(a)(i) (delivery) tube 1

1(a)(iii) arrow beneath the tube containing the mixture of alcohols 1

1(b) to cool 1

the gas into a liquid 1

1(c) to measure the temperature of the vapour / temperature of liquid would not be constant 1

1(d) E shown on the test-tube in water bath 1

1(e)(i) lighted splint ignites the liquid / test for water, e.g. add anhydrous copper(II) sulfate gives a negative result 1

1(e)(ii) melting / boiling point determination 1


2(a) all volume boxes completed correctly: 0, 13, 25, 38, 48, 59, 70, 79, 88, 96 3

2(b) origin plotted 1

other points correctly plotted 1

two smooth lines 1

labelled 1

2(c) Experiment 1 1

more concentrated / stronger acid / the acid has a lower pH 1


May/June 2017



2(d) volume of gas at 30 s 1

correct calculation of rate 1

unit: cm3 / s OR cm 3

s–1 1

2(e) all the magnesium will have reacted 1

2(f) faster reaction / increased rate 1

magnesium powder has a higher surface area 1

2(g) advantage: easy to use / quick 1


2(h) use of burette / pipette / gas syringe / weighed amount of magnesium / repeat experiment (and average) / clean the magnesium / remove oxide layer

1


3(a) chlorine 1

3(b)(i) iron(III) 1

hydroxide 1

3(b)(ii) green 1

precipitate 1

3(c) oxygen 1

3(d) catalyst 1

transition element compound / manganese oxide 1


May/June 2017



4 any 6 from: • crush lumps • pestle and mortar • weigh cassiterite • heat / reduce • with carbon / CO / more reactive metal, e.g. Zn • weigh tin • (mass of tin / initial mass) × 100 (%)

6

Documents

Published - Max Papers | Ultimate resource for …maxpapers.com/wp-content/uploads/2012/11/0620_s17_ms_all.pdfCHEMISTRY 0620/11 Paper 1 Multiple Choice (Core) May/June 2017 MARK SCHEME