OCR{i CHEMISTRY 1O JUNE 2OO4. Chains and Rings

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1 OCR{i RECOGNSNG AC EVEMENT OXFORD CAMBRDGE AND RSA EXAMNATONS Advanced Subsidiary GCE CEMSTRY Chains and Rings Thursday 1O JUNE 2OO4 Morning 2812 t hour Candidates answer on the question paper. Additional materials: Data Sheet for Chemistry Scientificalculator Candidate Name Centre Number Candidate Number TME t hour NSTRUCTONS TO CANDDATES o Write your name in the space above. r Write your Centre number and Candidate number in the boxes above.. Answer all the questions. o Write your answers in the spaces provided on the question paper.. Read each question carefully and make sure you know what you have to do before starting your answer. NFORMATON FOR CANDDATES. The number of marks is given in brackets [ ] at the end of each question or part question. o You will be awarded marks for the quality of written communication where this is indicated in the question. o You may use a scientificalculator.. You may use the Data Sheet for Chemistry.. You are advised to show all the steps in any calculations. FOR EXAMNER'S USE Question Number Max. Mark TOTAL 60 This question paper consists of 11 printed pages and 1 blank page. sp (SLM/GR) /6 o ocr 2004 Jt100t34241 Begistered Charity Number: [Turn over

2 2 Answer all the questions. Examinels This questionis about the compounds A-F below.,]/ \ / C:C / \ - A A,/ b--' \, r l t l t t t l -C-C-C-C-O O-C-C-C-C-O l t l t t t t l B C t t t t t t t t -C-C-C-C- -C-C-C-C- t t t t t t t l O r=_j \ / c:c / \ t-t,/ \ / \ F (a) Answer the following questions by referring to the compounds A-F. (i) What is the molecular formula of compound D?..t1 l (ii) What is the empirical formula of compound C?..111 (iii) Which two compounds are structural isomers of each other?. and...t1 l (iv) Which two compounds are cis-f rans isomers of each other?. and...t1 l (b) Compound E can be dehydrated to form compound A. Complete a balanced equation for this reaction. l t t l - C- C-C-C- t t t l O _> 2812 Jun04

3 3 (c) Compound C can be dehydrated to form a new compound, G, with the molecular formula, Cou.Suggest a structural formula and a name for G. Examine/s [Total: 7] [Turn over

4 4 2 alogenoalkanes, such as 1-chlorobutane, are hydrolysed with hot aqueous alkali, O-(aq), to form alcohols. Examinels (a) Describe, with the aid of curly arrows, the mechanism of the hydrolysis of 1-chlorobutane with O-(aq) ions to produce butan-1-ol. Show any relevant lone pairs of electrons and dipoles. c3c2c' -c -cl + c3c2cr-c-o + (b) Another halogenoalkane,, has a relative molecular mass o 127 and has the following composition by mass: C,37.8"/";, 6.3%; C,55.9"/". (i) Show that the empirical formula of compound is CroC/. t4l (ii) Deduce the molecular formula of compound. l2l (iii) Compound can also be hydrolysed with hot aqueous alkali to form butane-1.3-diol. Draw the structure of butane-1.3-diol. (iv) Deduce the structure of compound Jun04

5 (c) 1-Chlorobutane can also react with O- ions to form but-1-ene. 5 Examiner's (i) State a suitable solvent for this reaction..t1 l (ii) Name the type of reaction...t1 l (iii) Draw the structure of but-1-ene. (iv) Write a balanced equation for the reaction. (d) But-1-ene can undergo polymerisation. Draw a section of the polymer that can be formed from but-1-ene. Show two repeat units...t1 l (e) Amphetamine is a pharmaceutical that acts as a stimulant. lt increases the heartrate and dilates the air passages in the lungs. A possible reaction scheme for the preparation of amphetamine is shown below. l2l c, Br C, N,./ \./ C Ct + reagent J \-/ C Ct + product K (i) ldentify reagent J. (ii) (iii) ldentify product K. Suggest suitable conditions for this reaction Jun t11.. [Total: 1 B] ' [Turn over

6 6 3 (a) Many organic molecules show structural isomerism. State what is meant by the term structural isomerism. Examine/s,..t21 (b) lsomers 1,2 and 3, shown below, are unsaturated structural isomers of Cu.,o. \ / c-c / \ c3c2c' \ / c-c / \ c3c2 c'.c \ / c-c / \ c3c2 isomer 1 isomer 2 isomer 3 (i) Complete the boxes by drawing two other unsaturated structural isomers of Cr.,o. (ii) Name isomer 3. (iii) Draw the skeletal formula of isomer 2. t2l...t1 l

7 (c) There are several cycloalkanes that are structural isomers of Cu.'0. 7 Examiner's (i) Complete the boxes by drawing two other structural isomers of Cu.,o that are also cycloalkanes.,rc( C, \.r, \ t,c-c,,c C /\,C -.zct C, isomer L (ii) Name isomer L drawn in (c)(i). ethylcyclopropane l2l...t11 (iii) Draw the skeletal formula of isomer L. (d) fsomer L, Cs.,o, reacts with Ctrin the presence of UV light to produce the organic product C';C/. The reaction takes place in three stages: initiation, propagation and termination. (i) The reaction is initiated by the fission of Clr. State the type of fission involved. (ii) Write an equation to illustrate the fission of C/, in (dxi). (iii) The fission of C/, leads to a chain reaction involving two propagation steps. Complete the equations for the two propagation steps....t1 l Cu, o + -+.Css +.Cug [Total: 14] 2812 Jun04 [Turn over

8 8 Lavandulol, C101BO, is a fragrant oil which is found in lavender. The structural and the skeletal formulae of lavandulol are shown below. Examinels C. n -2"\C.C 2, -,-c>t't-o,.., l -,C:,/ rc " - \ -C structural formula skeletal formula (a) (i) ldentify two different functional groups in lavandulol. (ii) Why does lavandulol not have cis-trans isomerism?. and...t21 (b) Lavandulol, C,o.,uO,also reacts with bromine to form a saturated organic product...t11 State what you would see in this reaction and deduce the molecular formula of the organic product. observation....t1 l molecular formula...t21 (c) Lavandulol could be converted into an ester X, which is also found in lavender oil. { o tl C \r*. ester X State a reagent and a catalyst that could be used to form ester X from lavandulol. reagent.... t1 l catalyst Jun04

9 (d) Lavandulol can be oxidised to produce either compound Y or compound Z. 9 c20 co lavandulol c1o180 compound Y c1o160 compou nd 7 c,o,uo, (i) (ii) Write a balanced equation for the oxidation of lavandulol to produce compoundz. the molecular formulae given above and use [O] to representhe oxidising agent....t21 An infra-red spectrum of either compound Y or compound Z was obtained and was found to contain an absorption between cm-1. owever, there was no broad absorption between cm-1. By referring to your Data Sheet, use this information to deduce whether the infrared spectrum was of compound Y or of compoundz. Show your reasoning. The infra-red spectrum was of compound... because... [Total: 12] [Turn over

10 5 n this question, one mark is available for the quality of written communication. 10 Examinels Alkanes can be separated from crude oil because they have different boiling points. The table below shows the boiling points of some alkanes. alkane boiling point/'c Mr ethane propane butane 0 58 pentane methylbutane ,2-dimethylpropane Explain the variation in boiling points of the alkaneshown. tsl Explain why, in industry, alkanesuch as octane are processed by isomerisation. t3] lllustrate your answers by referring to suitablexamples. Write equations where appropriate. END of euestron PAPER Quality of Written Communication [1] [Total: 9]