$Pb \left( NO _{3}\right)_{2} \stackrel{673 K }{\longrightarrow} A + PbO + O _{2}$
$A \stackrel{\text { Dimerise }}{\longrightarrow} B$
| સ્તંભ $A$ | સ્તંભ $B$ |
| $(i) \;\mathrm{Na}_{2} \mathrm{O}$ | $(a)$ તટસ્થ |
| $(ii) \;\mathrm{Al}_{2} \mathrm{O}_{3}$ | $(b)$ બેઝિક |
| $(iii)\;\mathrm{N}_{2} \mathrm{O}$ | $(c)$ એસિડિક |
| $(iv)\;\mathrm{Cl}_{2} \mathrm{O}_{7}$ | $(d)$ ઉભયગુણી |