An introduction to A Level organic chemistry

8(a) biological activity [1] 1 8(b) rotates plane polarised light 5.0° in anticlockwise direction [1] 1 8(c) enantiomers [1] 1 8(d) racemic [1] 1 8(e) use of chiral catalyst [1] 1 8(f) CH and CH only in column one [1] 3 2 CH gives a doublet, CH gives a triplet [1] 2 doublet due to 1 proton on neighbouring carbons triplet due to 2 protons on neighbouring carbons [1] 8(g) 5 [1] 1 © Cambridge University Press & Assessment 2024 Page 11 of 12 8(h) 3 at pH 1 [1] at pH 3 AND or at pH 9 [1] at pH 14 [1] © Cambridge University Press & Assessment 2024 Page 12 of 12

5(a)(i) 1 5(a)(ii) the OH / NH groups / O atoms AND can hydrogen bond with water 1 5(a)(iii) C H N O F 1 33 35 2 5 5(a)(iv) 1 5(a)(v) different / better biological activity 1 5(b)(i) 16 / sixteen 1 5(b)(ii) M1: 4 / four 2 M2: proton exchange between NH / OH with D © Cambridge University Press & Assessment 2025 Page 12 of 17 5(c) groups reacting 2 • carboxylic acid • amide groups forming • (primary) alcohol • amine Any two [1] all four [2] Question Answer Marks