The order of negative electron gain enthalpy of $Li$,$Na$,$S$,$Cl$ is

Consider the following conversions:
$(i) \, O_{(g)} + e^- \to O_{(g)}^{-}, \Delta H_1$
$(ii) \, F_{(g)} + e^- \to F_{(g)}^{-}, \Delta H_2$
$(iii) \, Cl_{(g)} + e^- \to Cl_{(g)}^{-}, \Delta H_3$
$(iv) \, O_{(g)}^{-} + e^- \to O_{(g)}^{2-}, \Delta H_4$
Based on the given information,which statement is incorrect?

Which of the following processes is endothermic?

Which of the following arrangements for the three halogens $Cl$,$Br$,and $I$ when placed in the order of their increasing electron affinity is correct?

The electron gain enthalpy (with negative sign) of fluorine is less than that of chlorine due to:

What is the value of electron gain enthalpy of $Na^{+}$ if $IE_{1}$ of $Na$ is $5.1 \ eV$? .......... $eV$