CAIE A Level Chemistry 9701 · Chemical energetics

Chemical energetics: suggest question

Suggest4 marksStandard

The first electron affinity of chlorine is $-349$ kJ mol $^{-1}$ and that of oxygen is $-141$ kJ mol $^{-1}$ . Suggest, in terms of atomic structure and the factors affecting electron affinity, why the first electron affinity of chlorine is more exothermic than that of oxygen.

How this question is marked

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.

Suggest means: Apply what you know to an unfamiliar situation. There may be more than one acceptable answer. Reason from the principle you have learned to the new context, and say which principle you are using.

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