Question

Name three non-metals which have -1 valency.

Answer 1

Valency: Valency is defined as the number of electrons lose or gain by an atom to attain noble gas electronic configuration.

• The ions formed by accepting only one electron into their outermost shell are called monovalent electronegative ions.
• The elements of the halogen family require one electron to attain noble gas electronic configuration.
• Hence, the halogen family can show -1 valency.
• The elements whose ions have valency -1 are:

(i) Chlorine (Cl^-)

(ii) Bromine (Br^-)

(iii) Iodine (I^-)