Chemistry

UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS

GCE Ordinary Level

MARK SCHEME for the October/November 2010 question paper for the guidance of teachers

5070 CHEMISTRY

5070/42 Paper 4 (Alternative to Practical), maximum raw mark 60

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 must be read in conjunction with the question papers and the report on the examination.

•

CIE will not enter into discussions or correspondence in connection with these mark schemes.

CIE is publishing the mark schemes for the October/November 2010 question papers for most IGCSE, GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level syllabuses.

Page 2 1

Mark Scheme: Teachers’ version GCE O LEVEL – October/November 2010

Syllabus 5070

Paper 42

(a) (i) measuring cylinder (1) (ii) 44 (1) cm3 (iii) 0.0044 (1) moles (b) (i) 0.005 (1) moles (ii) Mg + H2SO4 → MgSO4 + H2 (1) magnesium + explanation (1) (c) (i) pops in a flame (1) (ii) 0.106 dm3 (1) [8]

2

(a) (i) final temperatures: 44, 32, 38 (2) rise in temp: 24, 12, 18 (1) (ii) rise in temperature or increased thermometer reading or wtte (1) (b) X – butanol, Y – ethanol, Z – propanol (2) (c) (i) propanol or Z (1) (ii) potassium manganate / permanganate or KMnO4 (1) purple to colourless (1) OR sodium dichromate or Na2Cr2O7 (1) orange to green (1) (d) (i) butanol or X (1) (ii) ester (1) [11] [1] [1] [1] [1] [1]

3 4 5 6 7

(b) (b) (a) (b) (a)

© UCLES 2010

Page 3 8 (a) 3.12 g (1) (b) (i) pink to

Mark Scheme: Teachers’ version GCE O LEVEL – October/November 2010

Syllabus 5070

Paper 42

(ii) colourless (1) (c) 25.2 31.1 48.3...