HALOGENATION OF PROPANONE

Hint

For an elementary reaction of the form, aA + bB → cC,

Example:

For the elementary reaction, O₃ + NO → NO₂ + O₂

r = -d[O₃]/dt = -d[NO]/dt = +d[NO₂]/dt = + d[O₂]/dt

r = k[O₃]¹[NO]¹ = k[O₃][NO]

Overall Rate of Consumption of Iodine {-d[I₂]/dt}

For the proposed mechanism

The overall rate of consumption of iodine can be expressed as

-d[I₂]/dt = + k₁[H⁺][P_k] + k_-1[P_e][H⁺] + k₂[P_e][I₂]

-d[I₂]/dt = - k₂[PI][H⁺][I^-]

-d[I₂]/dt = + k₂[P_e][I₂]