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?
Solution
A reaction is second order in A and first order in B.
Differential rate equation:- 
(ii) On increasing the concentration of A three times i.e. 3A:
Rate = k[3A]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:
Rate1= k[2A]2[2B]=k(4x2)[A]2[B]=8k[A]2[B]=8 (Rate) , i.e. 8 times the initial rate.
