Chemistry - Complete d-block Question with Solution | TestHub

Transition metals show variable oxidation states, due to which they can perform as catalyst. $$\begin{array}{rl}& \text{ e.g., }2{\mathrm{SO}}_2+{\mathrm{O}}_2\underset{\text{ (catalyst) }}{\stackrel{{\mathrm{V}}_2{\mathrm{O}}_5}{⟶}}2{\mathrm{SO}}_3\\ & {\mathrm{SO}}_2+\stackrel{+5}{{\mathrm{V}}_2}{\mathrm{O}}_5⟶{\mathrm{SO}}_3+\stackrel{+4}{{\mathrm{V}}_2}{\mathrm{O}}_4\\ & \stackrel{+4}{{\mathrm{V}}_2}{\mathrm{O}}_4+{\mathrm{O}}_2⟶\stackrel{+5}{V}{\mathrm{V}}_5\\ & \end{array}$$