Chlorine undergoes disproportionation in alkaline medium as shown below :
$\begin{aligned} & \mathrm{a} \mathrm{Cl}_2(\mathrm{~g})+\mathrm{bOH}^{-}(\mathrm{aq}) \rightarrow \mathrm{cClO}^{-}(\mathrm{aq})+\mathrm{dCl}^{-}(\mathrm{aq}) \\ & +\mathrm{e}_2 \mathrm{O}(l)\end{aligned}$
The values of a,b,c and d in a balanced redox reaction are respectively :