Compare5 marksStandard
Two organic compounds, butanone and propanal, are each treated with alkaline aqueous iodine. Compare the expected observations for the two compounds and explain the difference in terms of their structures.
CAIE A Level Chemistry 9701 · Carbonyl compounds
Carbonyl compounds: compare question
How this question is marked
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Compare means: Give similarities or differences between two things, and say which side each point belongs to. Write each point as a pair, for example: A is X, whereas B is Y. Two separate descriptions rarely earn the marks.
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