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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?
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Solution
(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
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