Answer:
The correct answer is option A.
Explanation:
Step 1 : Slow
[tex]ClO^-(aq) + H_2O(l)\rightarrow HClO(aq) + OH^-(aq)[/tex]
Step 2: Fast
[tex]I^-(aq) + HClO(aq)\rightarrow HIO(aq) + Cl^-(aq)[/tex]
Step 3: Fast
[tex]OH^-(aq) + HIO(aq)\rightarrow H_2O(l) + IO^-(aq)[/tex]
When there is a recation which is taking place in a more that single steps than the rate of the reaction is determined by the slowest step occurring in the reaction mechanism.
So, according to question step 1 is slow step which means that rate of the reaction will be :
[tex]R=k[ClO^-][H_2O][/tex]