Question

Show the formation of oxide ion.(Atomic number of oxygen = 8)

Answer 1

Definition of valency.

The number of valence electrons lost or gained by an atom in order to attain stability is called valency.

The atomic number of oxygen = 8

Electronic configuration = 2,6

since oxygen has six electron in its outermost shell, it does not have stable electronic configuration.

oxygen gain two electrons and achieve the stable configuration as 2,8

$$\begin{gathered} \mathrm{O}+2{\mathrm{e}}^{-}\to {\mathrm{O}}^{2-} \\ 2,62,8 \end{gathered}$$

An oxygen atom($\mathrm{O}$) has 8 protons and 8 electrons. On gaining two electron, it becomes an oxide ion (${\mathrm{O}}^{2-}$).