Chemistry - PERIODIC TABLE Question with Solution | TestHub

$(\mathrm{P})\mathrm{Be}\to {\mathrm{Be}}^{-}$

$\mathrm{EC}={\mathrm{ns}}^2$ (fully filled)

$\Delta \mathrm{H}=+\mathrm{ve}$ (Endothermic)

$(\mathrm{P})⟶1,3$

(Q) ${\mathrm{O}}^{-}\to {\mathrm{O}}^{-2}$

Here, second Electron gain enthalpy is always positive or endothermic.

$(\mathrm{Q})\to 1,3$

(R) $\mathrm{F}\to {\mathrm{F}}^{-}$ Electron gain enthalpy $=-\mathrm{ve}($ exothermic $)$

$\mathrm{R}\to 2,4$

(S) $\mathrm{Cl}⟶{\mathrm{Cl}}^{-}$

Electron gain enthalpy $=-\mathrm{ve}$ (Exothermic)

It has the highest electron gain enthalpy in periodic table.

$\mathrm{S}\to 2,4,5$