Chemistry - PERIODIC TABLE Question with Solution | TestHub

The first ionization energy ($I{E}_1$) of an anion X⁻ is numerically equal to the electron affinity ($EA$) of the neutral atom X, such that $\Delta H_{eg}=-I{E}_1(X^{-})$. For halogens, the magnitude of $\Delta H_{eg}$ follows the order $Cl>F>Br>I$. From the provided list, the values $+349$, $+328$, $+325$, and $+295kJ/mol$ correspond to the $I{E}_1$ of $C{l}^{-}$, $F^{-}$, $B{r}^{-}$, and $I^{-}$ respectively. Therefore, for the fluorine atom, $I{E}_1(F^{-})=328kJ/mol$, making the $\Delta H_{eg}$ value $-328kJ/mol$.