Question

Discuss the pattern of variation in the oxidation states of (i) $B$ to $Ti$ and (ii) $C$ to $Pb$.

Answer 1

(i) B shows $+3$ oxidation state. Other group 13 elements s show $+1$ and $+3$ oxidation state.
On moving down the group 13, the stability of $+1$ oxidation state increases and the stability of $+3$ oxidation state decreases due to inert pair effect.
B and Al show $+3$ oxidation state, $Ga$ and $In$ show $+1$ and $+3$ oxidation states and $Tl$ mainly shows $+1$ oxidation state.
(ii) Group 14 elements show $+2$ and $+4$ oxidation states. The stability of $+2$ oxidation state increases and the stability of $+4$ oxidation state decreases due to inert pair effect. $C$ and $Si$ mainly show $+4$ oxidation state, $Ge$ and $Sn$ show $+2$ and $+4$ oxidation state and $Pb$ mainly shows $+2$ oxidation state.