CAIE A Level Chemistry 9701 · An introduction to organic chemistry
Explain what is meant by (i) a chiral centre and how it gives rise to optical isomerism, and (ii) the origin of geometrical (cis/trans) isomerism in alkenes. In your answer, give an example of a molecule that exhibits each type of isomerism.
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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