Answer:
The answer is "Base".
Explanation:
Given equation:
[tex]SO_3\ (g)+ O^{2-}\ (aq) \longrightarrow SO_4^{2-}\ (aq)[/tex]
In the above-given chemical equation, the [tex]O^{-2}[/tex] is the lewis base which is used to donate an electron pair to the central atom of [tex]SO_3[/tex] to form [tex]SO_{4}^{-2}[/tex].
It is any substance like the [tex]OH^-[/tex] ion which might give a pair of non-bound electrons. Hence, it is an electron-pair donor. Throughout the theory of Lewis acid is an ion or molecule which accepts a pair of nonbonding electrons of value, that's why the base is the correct answer.
