(a)[3]
State and use the appropriate electrode potentials, $E^\ominus$, to form two equations that illustrate how $\text{MnO}_2$ catalyses this reaction.
(b)[1]
At these conditions, the reaction is first order with respect to hydrogen peroxide, and the rate constant, $k$, is $2.0 \times 10^{-6}\,\text{s}^{-1}$ at $298\,\text{K}$. Calculate the initial decomposition rate for a $0.75\,\text{mol dm}^{-3}$ hydrogen peroxide solution at $298\,\text{K}$.
(c(i))[1]
State the meaning of the term rate-determining step.
(c(ii))[1]
Use this mechanism to derive a balanced equation for this reaction.
(c(iii))[1]
Deduce the reaction order with respect to each of these: $\text{H}_2\text{O}_2$, $\text{I}^-$, $\text{H}^+$.