Question

what is difference between valence and valency

Answer 1

valency is the ability of an atom to lose or gain electrons while valence electons is the no. of electrons in its outermost shell. valency = combining capacity of an atom expressed as the no. of single bondsthe atom can form or the no. of electrons an element gives up or accepts when reacting to form a compound.

Answer 2

valence is number of atoms in outermost shell of the element whereas valency is the combining power of the element meaning how it joins with other atoms(bonds)