Question

4(c) Name three non-metals/group of non-metals which have -2 valency.

Answer 1

• The ions formed by accepting only two electrons into their outermost shell are called bivalent electronegative ions.
• The elements which have six electrons in their outermost shell can easily accept two-electron to attain a stable octet configuration.
• The non-metals/group of non-metals which have valency -2 are:

(i) Sulphate (${\mathrm{SO}}_4^{2-}$)

(ii) Oxide (${\mathrm{O}}^{2-}$)

(iii) Carbonate (${\mathrm{CO}}_3^{2-}$)