Question

Valency - It is the combining capacity of an
atom Value st Waleney wantity songs from l-4.
Elements having woriebt selencies.
Certain elements to like Cu, Fe, Son Pb etc are
known to have variable valencies. In order to
deferenciete them, there is a rule, which is as
hollows:​

Answer 1

Answer:

Valency is the combining capacity of an atom of an element with atoms of other elements to form molecules.

VARIABLE VALENCY

Some elements exhibit more than one valency. They're said to have variable valency.

Examples : Iron, copper, tin, lead, sulphur, phosphorus.

In the case of the metals exhibiting variable valency, we represent the lower valency by adding the suffix 'ous' to the name of the metal; to represent the higher valency the suffix 'ic' is attached to the name of the metal.

For example , the metal iron has valencies +2 and +3. For the lower valency (+2) we write ferrous (Fe2 +) and for the higher valency (+3) we write ferric (Fe3 +).