Question

Question: The reaction of tert-butyl chloride with methanol

Is found to follow the rate equation

(a) What is the kinetic order with respect to tert-butyl chloride?

(b)What is the kinetic order with respect to methanol?

(c)What is the kinetic order overall?

Short answer

Answer

(a) First order

(b) Zero order

(c) First order

Step-by-step solution

Rate equation

It may be defined as the relationship between the concentrations of the reactants and the observed reaction rate. Each reaction has its rate equation,which may be determined experimentally by altering the concentration of the reactants and then measuring the change in rate.

Consider a general reaction of the type :$aA+bB\to Products$

The reaction rate is usually proportional to the concentrations of the reactants and [B] ,which are raised to powers and ,respectively. The rate expression can be written asfollows:

$rate=k_r\left[{\left[A\right]}^a{\left[B\right]}^b\right]$

, where rate K_rconstant.

Order of a reaction

The order of a reaction may be defined as the sum of the exponents to which the concentration terms in the rate law are raised to express the observed rate of reaction.

Fromthegeneral equation of the type,$aA+bB\to Products$, the rate expression can be written as, role="math" localid="1651750958241" $rate=k_r\left[{\left[A\right]}^a{\left[B\right]}^b\right]$.

and are called the orders of the reaction with respect to and . Depending on whether is equal to , the reactions are said to be of zero order, first order, second order, and third order, respectively.

Explanation

(a)From the rate equation rate=,$k_r\left[{\left(C{H}_3\right)}_{3}C-Cl\right]$ it is evident that the order with respect totert-butyl chloride is first order.

(b) The rate law is independent of the concentration of methanol. Hence,theorder with respect to methanol is zero order.

(c) The overall order for the reaction is first order since the rate law is directly proportional to the concentration of tert-butyl chloride only.