Question

Show the formation of sulphide ion.(Atomic number of sulphur =16)

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 sulphur = 16
• Electronic configuration = 2,8,6
• since sulphur has six electrons in its outermost shell, it does not have a stable electronic configuration.
• Sulphur gains two electrons and achieves the stable configuration as 2,8,8
• $$\begin{gathered} \mathrm{S}+2{\mathrm{e}}^{-}\to {\mathrm{S}}^{2-} \\ 2,8,62,8,8 \end{gathered}$$
• A sulphur atom($\mathrm{S}$) has 16 protons and 16 electrons. On gaining two-electron, it becomes a sulphide ion (${\mathrm{S}}^{2-}$).