ICSE Class 9 Answered

Valency denotes the combining capacity of the atom of an element.

It is equal to the number of electrons an atom can donate or accept or share.

It is determined by the number of valence electrons present in the outermost shell.

If you want to find a valency whether it’s a metal or an non-metal then see there valence electrons

i.e. the number of electrons in the outer most shells then see if the valency is 1,2 or 3

then it would be an metal thus loosing 1,2,3 electrons and having:+1,+2, 3+ valency respectively.

If the number of electrons are in the outer most shell are 5, 6, 7 then that element can accept 1, 2 or 3 electrons having -1, -2, -3 valency

and that element will show non metallic character.