Question

Which of the following oxidation states are the most characteristic for lead and tin respectively?

(a) +2,+4

(b) +4,+4

(c) +2,+2

(d) +4, +2

Answer 1

The correct option is : (a) +2,+4

Explanation:

When ns² electrons of outermost shell do not participate in bonding then these ns² electrons are called inert pair and the effect is called inert pair effect. Due to this inert pair effect Ge, Sn and Pb of group IV have a tendency to form both +4 and +2 ions. Now the inert pair effect increases down the group, hence the stability of M²⁺ ions increases and M⁴⁺ ions decreases down the group. For this reason, Pb²⁺ is more stable than pb⁴⁺ and Sn⁴⁺ is more stable than Sn²⁺.