# Can a a compound with a lone pair of electrons such as NH_3 be a nucleophile?

'Nucleophile' means 'nucleus loving' and is any group that attaches to a species with a positive charge, such as $R {b}^{+}$, $C {s}^{+}$ or $F {r}^{+}$.
$N {H}_{3}$ (ammonia) can be a nucleophile, as can other Lewis bases, as they are electron donors. A Lewis base is any compound that reacts with a Lewis acid, such as ${H}_{3} {C}^{-}$, ${H}_{2} {N}^{-}$ or ${H}_{2} S {b}^{-}$. A Lewis acid is any substance that reacts with a Lewis base, such as $L {i}^{+}$, $N {a}^{+}$, ${K}^{+}$, $R {b}^{+}$ or $C {s}^{+}$.