A reaction is first order in A and second order in B:
Write the differential rate equation.
How is the rate affected on increasing the concentration of B three times?
How is the rate affected when the concentrations of both A and B are doubled?
Rate =k[A][3B]2=9k[A][B]2 Rate of reaction becomes 9 times
Rate =k[2A][2B]2=8k[A][B]2 Rate of reaction becomes 8 times.