Question

(A-2,8,8,1; B-2,4; C-2,8,7; D-2,8,8) Which pair of elements may form a covalent bond

Answer 1

Answer:

B and C [Carbon and Chlorine]

This is because B is tetravalent, with a strong affinity for covalency. Hence, B will be one of the elements.

The other element cannot be D, since D is a noble gas due to its zero valency status.

It cannot be A either, since A is monovalent electropositive, a sign of metallic character. Metals do not usually form covalent bonds.

Hence it is C, which is a non-metal as well.

This can be verified as B and C are Carbon and Chlorine respectively. They form the compound Carbon tetrachloride or CCl4.