Question

What do you mean by the valency of a substance?

Answer 1

valency is defined as the number of electrons that can be gained or donated during the compound formation. for e.g.. In the formation of nacl na donated 1 elec . and cl gains 1 elec .therefore the valency of na is +1 and valency of cl. is -1

Answer 2

Valency is the combining capacity of an element.

All the elements usually donate or obtain electrons to obtain the nearest noble gas configuration.

Example

Chlorine atom needs one electron to become stable and therefore it has a valency of -1

While sodium donates an atom to become stable and therefore it has a valency of +1



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