Question

using your pseudo-rate constant and concentrations/orders that you determine for acetone and H+, determine the us actual rate constant for the iodination of acetone,

Answer 1

Acid-catalyzed reaction between iodine and acetone in aqueous solution:

CH₃COCH₃ + I₂ ------> CH₃COCH₂I + HI

The rate of this reaction is expected to depend on the concentrations of the two reactants.

Rate = k[CH₃COCH₃]^m [I₂]ⁿ[H⁺]^o

Where m, n and o are the orders of the reaction with respect to acetone, iodine and acid respectively and k is the rate constant for the reaction.

The rate of this reaction can be expressed as change in the concentration of I₂

rate = - Δ[I₂]/ Δt

Important characteristic of this reaction is that it turns out to be zero-order in I₂ concentration.

Actually the rate of the reaction does not depend on [I₂] .Since the rate of reaction does not depend on [I₂], we can study the rate by simply making I₂ the limiting reagent present in a large excess of acetone. The orders of the reaction with respect to acetone is 1, with respect to iodine is zero and with respect to H⁺ is1.

Rate constant(k ) = rate/[CH₃COCH₃]^m [I₂]ⁿ[H⁺]^o