Assign $A$,$B$,$C$,$D$ from the given type of reaction.
$CuSO_4 + Zn_{(s)} \longrightarrow ZnSO_4 + Cu$

In the balanced chemical reaction $IO_3^- + aI^- + bH^+ \longrightarrow cH_2O + dI_2$,the values of $a, b, c,$ and $d$ are respectively:

Chlorine is used to purify drinking water. Excess of chlorine is harmful. The excess of chlorine is removed by treating with sulphur dioxide. Present a balanced equation for this redox change taking place in water.

What is the equivalent weight of $SnCl_{2}$ in the following reaction: $SnCl_{2} + Cl_{2} \longrightarrow SnCl_{4}$?

In the reaction of oxalate with permanganate in acidic medium,the number of electrons involved in producing one molecule of $CO_2$ is

Balance the following redox reactions by the ion-electron method:
$(a)$ $MnO_4^-(aq) + I^{-}(aq) \rightarrow MnO_2(s) + I_2(s)$ (in basic medium)
$(b)$ $MnO_4^-(aq) + SO_2(g) \rightarrow Mn^{2+}(aq) + HSO_4^-(aq)$ (in acidic solution)
$(c)$ $H_2O_2(aq) + Fe^{2+}(aq) \rightarrow Fe^{3+}(aq) + H_2O(l)$ (in acidic solution)
$(d)$ $Cr_2O_7^{2-} + SO_2(g) \rightarrow Cr^{3+}(aq) + SO_4^{2-}(aq)$ (in acidic solution)