Question

A reaction is second order in A and first order in B.

(i) Write the differential rate equation.

(ii) How is the rate affected on increasing the concentration of A three times?

(iii) How is the rate affected when the concentrations of both A and B are doubled?

 

Answer 1

(i) A reaction is second order in A and first order in B.

Differential rate equation:− `Rate=(-d[R])/dt=K[A]^2[B]`

(ii) On increasing the concentration of A three times i.e. 3A:

`Rate=k[3A]^2[B]=9k[A]^2[B]=9k[A]^2[B]=9(Rate)` , i.e. 9 times the initial rate.

(iii) On increasing the concentration of A and B as 2A and 2B:

`Rate=k[2A],^2[2B]=k(4xx2) i.e. 8 times the initial rate.[A]^2[B]=8k[A]^2[B]=8(Rate)` i.e. 8 times the initial rate