Skip to content
CIE Nov 2014 v3 Paper 4 Q9
Answers available below
Show answer
Question
1
2
3
4
5
6
7
8
9
![(a) Polymers can be formed by addition or condensation polymerisation. Complete the table. 18 method of polymerisation polymer nylon PVC (polychloroethene) Terylene PMT [1] (b) Nomex is a polymeric material with excellentame-resistant properties. It contains a polymer made from the two monomers shown below. H2N NH2 HO2C CO2H Draw the structure of the polymer showing two repeat units. The linkages between monomer units should be shown fully displayed. (c) Proteins are natural polymers. Explain what is meant by the primary structure of a protein.[1] [2]UCLES 2014 9701/43/O/N/14<br />
(d) Use the diagram to show an example of how the -helix secondary structure in proteins is stabilised. 19 PMT[2] (e) The tertiary structure of a protein is destroyed during the process of denaturation. Explain how this can occur by (i) the addition of alkali,(ii) the addition of Hg2+ ions,(iii) heating to 70 C.[3] [Total: 9]UCLES 2014 9701/43/O/N/14 [Turn over<br />](https://learnah.org/wp-content/uploads/2018/08/November_2014_v3_QP_-_Paper_4_CIE_Chemistry_A-level_9-0.jpg)
![Page 11 Mark Scheme Syllabus Paper Cambridge International A LevelOctober/November 2014 9701 43 (c) (i) structures of the following aldehydes: CHO CHO CHO CHO two correct structures = 1 mark two further correct structures1 mark (ii) 3-methylbutanal (iii) pentanal 5 absorptions 2-methylbutanal 5 absorptions dimethylpropanal 2 absorptions PMT [6] (a) nylon, terylenecondensation; PVCadditionall three correct [1] (b) correct fully displayed formula of -CO-NH- unit correct polymer structure [2] (c) sequence / order of amino acids (in the polypeptide chain) (d) hydrogen bond C=O and N-H in two different amino acids in the backbone diagramCambridge International Examinations 2014 [1] [2]<br />
PMT [3] Page 12 Mark Scheme Syllabus Paper Cambridge International A LevelOctober/November 2014 9701 43 (e) (i) disrupts hydrogen/ionic bonds as COOH/NH3 is deprotonatedNH2 + H2O linked to hydrogen / ionic bond disrupted + H2O linked to hydrogen / ionic bond disrupted OR NH3 + OH ORCOOH + OHCOO (ii) Hg 2+ interferes with/breaks the disulfide bond / bridge not sulfite, sulfate, sulfur, sulfide OR -S-S- shown with Hg in an equation OR disrupting ionic interactions linked to carboxyl / COO groups 2+ (iii) (Heat to 70 C) breaks the van der Waals forces / hydrogen bondingCambridge International Examinations 2014<br />](https://learnah.org/wp-content/uploads/2018/08/November_2014_v3_MS_-_Paper_4_CIE_Chemistry_A-level_9-0.jpg)
