Chemistry 9701 · AS & A Level · 3.1

3.1 — practice question

(a)[1]

Define the enthalpy change of atomisation, $\Delta H_{at}$.

(b)[1]

Define the first electron affinity, EA.

(c)[2]

Explain why chlorine's first electron affinity is more exothermic than iodine's first electron affinity.

(d)[2]

The enthalpy change for the reaction $\text{Cl}_2\text{(g)} + 2e^- \rightarrow 2\text{Cl}^-\text{(g)}$ is $-486\,\text{kJ mol}^{-1}$. The first electron affinity of chlorine is $-364\,\text{kJ mol}^{-1}$. Calculate the enthalpy change of atomisation of chlorine. $\Delta H_{at}$ of chlorine $= \ldots\,\text{kJ mol}^{-1}$.

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