Question

Why PbCl2 is more stable than SnCl2 ?

Answer 1

The stability of higher oxidation state decrease down the group whereas the stability of lower oxidation state increase down the group. This trend is the consequence of inert pair effect due to which two electron of lead in s orbital do not participate in chemical bonding. Hence Pb shows +2 oxidation state predominantly.

Whereas no such effect occur in Sn and hence it prefer to form SnCl4 in comparison of SnCl2. 

Answer 2

The stability of higher oxidation state decrease down the group whereas the stability of lower oxidation state increase down the group. This trend is the consequence of inert pair effect due to which two electron of lead in s orbital do not participate in chemical bonding. Hence Pb shows +2 oxidation state predominantly.

Whereas no such effect occur in Sn and hence it prefer to form SnCl4 in comparison of SnCl2.