Chemistry - Chemical Kinetics Question with Solution | TestHub

The reduction of peroxydisulphate ion by I ion is expressed by ${\mathrm{S}}_2{\mathrm{O}}_8^{2-}+3{\mathrm{I}}^{-}\to 2{\mathrm{SO}}_4^{2-}+{\mathrm{I}}_3^{-}$. If rate of disappearance of ${\mathrm{I}}^{-}$ is $9/2\times 10^{-3}\mathrm{mol}$ lit ${}^{-1}$ ${\mathrm{s}}^{-1},$ what is the rate of formation of $2{\mathrm{SO}}_4^{2-}$ during same time?