A reaction is first order in A and second order in B
(i) Write the differential rate equation.
(ii) How is the rate affected on increasing the concentation of B three times ?
(iii) How is the rate affected when the concentration of both A and B are doubled ?

Explanation

(i) Rate `=K[A]^(1)[B]^(2)`
Differential rate reaction
`(-d[R])/(dt) =K[A]^(1)[B]^(2)`
(ii) Rate ' `=K[A][3B]^(2)`
Rate ' `=9R`
(iii) Rate "`=K[2A][2B]^(2)`
`=8K[A][B]^(2)`
Rate''`=8R`.