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C2 2.7 Electrolysis
Using Exam pro items to support successful outcomes
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• Learners will be able to test their progress against learning outcomes using questions from past AQA GCSE examinations
• C2 2.7
Foundation Tier- June 12, 4
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Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Mark scheme- Foundation
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Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Q Answer Extra Information Mark (a)(i) Cryolite 1(a)(ii) Lower the melting point of the aluminium
oxide1
(b)(i) Opposite charges or oxide ions are negativeAttract
11
(b)(ii) Carbon 1
(b)(iii)
Reacts with oxygen or forms carbon dioxide Accept burns 1
(c) Structure mark:Either Al (atoms) in layers/rows
Or alloy (atoms) not in layers / rows
Sliding mark:either so (Al layers) can slideOr so (alloy) layers cannot slide
Accept Al (atoms) all the same sizeAllow Al (atoms) in linesAccept different sizes of atoms in alloyAllow alloy (atoms) not in lines
1
1
Total 8
Higher Tier June 12, 5
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Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Mark scheme- Higher
Version 2.0
Copyright © AQA and its licensors. All rights reserved.
• C2 2.7
Q Answer Extra Information Mark(a) 52.9 (411765/53 ) Correct answer with or without
working = 2 marksIf answer is incorrectAllow 2 x 27 = 54 or 27/102 x 100Or 26.5 for 1 mark
2
(b)(i) Because it lowers the melting point ( of the aluminium oxide)So less energy is needed ( to melt it)
Allow lowers the temperature needed.Do not accept lowers boiling pointAccept so that the cell / equipment does not melt.
1
1
(b)(ii) 2 O2- on left hand side4e- on right hand side
Accept correct multiples or fractionsAccept - 4e- on left hand side
11
(b)(iii) Because the electrode reacts with oxygen orBecause the electrode burnsTo form carbon dioxide or electrode made from carbon / graphite
1
1
8
• C2 2.7
