Which terms are exothermic for the formation of NaF(s)?

(P) $\mathrm{Na}\left(g\right)\to {\mathrm{Na}}^{+}\left(g\right)+e^{-}$

(Q) $\mathrm{F}\left(g\right)+e^{-}\to {\mathrm{F}}^{-}\left(g\right)$

(R) ${\mathrm{Na}}^{+}\left(g\right)+{\mathrm{F}}^{-}\left(g\right)\to \mathrm{NaF}\left(\mathrm{g}\right)$

Chemical reactions that release energy in the form of heat or light are known as exothermic reactions. These reactions, which are the antithesis of endothermic reactions, are expressible in chemical equations.

The Exothermic reactions are,

(Q) $\mathrm{F}\left(g\right)+e^{-}\to {\mathrm{F}}^{-}\left(g\right)$

(R) ${\mathrm{Na}}^{+}\left(g\right)+{\mathrm{F}}^{-}\left(g\right)\to \mathrm{NaF}\left(\mathrm{g}\right)$

Due to the electron's attraction to the nucleus, when an atom gains an electron, the energy change is exothermic.