Question

The iodide-catalyzed decomposition of hydrogen peroxide is thought to proceed by a four-step mechanism:

H2O2(aq) + I-(aq) --> HOI(aq) + OH-(aq) (slow)

HOI(aq) + OH-(aq) --> H2O(l) + OI-(aq)

OI-(aq) + H2O2(aq) --> HOOI(aq) + OH-(aq)

HOOI(aq) + OH-(aq) --> H2O(l) + O2(g) + I-(aq)

(a) If the first step of this mechanism is rate-determining (slow), choose the correct rate law for the overall process.

oRate = k [H2O2]2

oRate = k [I-] [H2O2]

oRate = k [H2O2] [H2O2]

oRate = k [HOI] [H2O2]

oRate = k [I-] [HOI]

oRate = k [H2O2]2 [H2O2]

(b) Choose the correct chemical equation for the overall process.

o H2O2(aq) + I-(aq) --> HOI(aq) + OH-(aq)

o HOI(aq) + OH-(aq) --> H2O(l) + OI-(aq)

o 2 H2O2(aq) --> 2 H2O(l) + O2(g)

(c) Identify an intermediate in the reaction.

oHOI

oH2O

oH2O2

oI-

(d) Identify the catalyst in the reaction.

oHOI

oI-

oH2O2

oH2O

(e) Identify a reactant in the reaction.

oH2O

oHOI

oH2O2

oI-

(f) Identify a product in the reaction.

oHOI

oI-

oH2O

oH2O2

Answer 1