A reaction is second order with respect to a reactant. How is the rate of reaction affected if the concentration is

(i) doubled (ii) reduced to half

Let suppose reaction

A B;


having rate law, Rate = K [A]2


(i) If the concentration of A is doubled then the rate will affect by the square of concentration i.e. rate will become 22 = 4 times.


(ii) If the concentration of A is halved then the rate will affect the square of concentration i.e (1/2)2 = 1/4 times.


(i) Rate becomes 4 times of initial Rate (ii) Rate becomes 1/4 times of initial Rate


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