Mark Scheme (Results) November 2009

Transcription

1 Scheme (Results) November 2009 IGCSE IGCSE Chemistry (4335) Paper F Edexcel Limited. Registered in England and Wales No Registered Office: One90 High Holborn, London WCV 7BH 4335_F Nov 2009 i

2 Edexcel is one of the leading examining and awarding bodies in the UK and throughout the world. We provide a wide range of qualifications including academic, vocational, occupational and specific programmes for employers. Through a network of UK and overseas offices, Edexcel s centres receive the support they need to help them deliver their education and training programmes to learners. For further information, please call our GCE line on , our GCSE team on , or visit our website at If you have any subject specific questions about the content of this Scheme that require the help of a subject specialist, you may find our Ask The Expert service helpful. Ask The Expert can be accessed online at the following link: Alternately, you can speak directly to a subject specialist at Edexcel on our dedicated Science telephone line: (If you are calling from outside the UK please dial and state that you would like to speak to the Science subject specialist). November 2009 Publications Code UG All the material in this publication is copyright Edexcel Ltd _F Nov 2009 ii

3 S E C T I O N A a M S b M O c M Accept Alkali metals d M 2 e M Al / aluminium TOTAL 5 2 a M hydrocarbons M2 heated M3 distillation M4 top M5 condenses b M carbon dioxide Accept answers in either order. Award mark for two correct formulae. M2 water TOTAL 7 3 a i M copper ii M sodium / copper iii M iron iv M copper 3 b M cross in box 2 M2 cross in box 3 TOTAL _F Nov 2009

4 4 a M white M2 colourless M3 decomposition b M ammonium chloride c i M white precipitate / solid / suspension ignore powder / crystals ii M ammonia / NH 3 TOTAL 6 5 a M (dilute) sulphuric acid water M zinc sulphate M2 + carbon dioxide (gas) M2 complete + + equation (solid) zinc carbonate zinc sulphate b M limewater M2 turns milky c M heat / increase the temperature M2 use powdered/smaller pieces(of zinc Any two for each carbonate) M3 use more concentrated (sulphuric) acid d i M carbonic (acid) ii M cross in box 2 iii M orange / yellow TOTAL _F Nov

5 6 a M limestone / calcium carbonate Either way round M2 coke / carbon M3 (hot) air M4 slag / calcium silicate Award mark for D M5 iron and E in reverse order b i M C + O 2 CO 2 ii M carbon + carbon dioxide carbon monoxide iii M loss of oxygen Accept gain of electrons c i M all formulae and CaCO 3 (s) CaO(s) + CO 2 (g) balancing correct M2 state symbols correct ii M CaSiO 3 TOTAL 7 a M (hydrated) iron(iii) oxide b M air / oxygen answers in either M2 water / moisture order c M oil / grease M2 galvanising / zinc coating Accept enamel TOTAL 5 8 a M black M2 blue Reject green b i M to neutralise/use up/react with all the acid ii M to remove the solid / copper oxide iii M to remove/evaporate (some of) the water Accept so crystals form iv M to dry the crystals / absorb water TOTAL 6 SECTION A TOTAL: 55 MARKS 4335_F Nov

6 S E C T I O N B 9 a M (electron) /836 / negligible Accept value in range /2000 to /800 and to Ignore zero M2 (neutron) 0 M3 (proton) M4 (proton) + b i M (number of) protons and neutrons M2 35 ii M 8 c i M 5 ii M isotopes TOTAL 9 0 a M white M2 blue b i M fractional M2 distillation ii M different boiling points / boiling point of propanone lower than that of water iii M heat / boil M2 propanone boils/collects (first) M3 stop collecting liquid above 56 C Accept wording that indicates that water collected separately or not at all c M cross in column box 4 M2 cross in column 2 box 2 TOTAL _F Nov

7 a M loses an electron/electrons M2 Na + b M gains two electrons M2 O 2 c M sodium oxide M2 Na 2 O TOTAL 6 2 a M (bromine) liquid M2 grey / black b i M any indication of chlorine in left hand tube ii M hydrogen / H 2 iii M brine / sodium chloride solution / NaCl(aq) Accept concentrated/saturated NaCl Ignore sea water c i M chlorine + sodium bromide M reagents 2 M2 bromine + sodium chloride M2 products ii M displacement / redox Accept reduction / oxidation Ignore substitution iii M (chlorine) more reactive (than bromine) TOTAL _F Nov

8 3 a M double bond / C=C / not all bonds are single b M contains bromine / another element/atom does not contain only carbon and hydrogen c M B and E d M A and B / A and E / C and F e M alkane(s) M2 C n H 2n+2 Accept other symbols such as x f M yellow / orange / brown M2 colourless / decolorised Ignore clear If only colourless stated, assume it is final colour g i M F ii M poly(ethene) / polyethene / polythene iii M addition TOTAL SECTION B TOTAL: 45 MARKS PAPER TOTAL: 00 MARKS 4335_F Nov

9 Further copies of this publication are available from International Regional Offices at For more information on Edexcel qualifications, please visit Alternatively, you can contact Customer Services at or on Edexcel Limited. Registered in England and Wales no Registered Office: One90 High Holborn, London, WCV 7BH