For reaction aA → xP, when [A] = 2.2 mM, the rate was found to be 2.4 mMs–1. On reducing concentration of A to half, the rate changes to 0.6 mMs–1. The order of reaction with respect to A is :
(a) 1.5
(b) 2.0
(c) 2.5
(d) 3.0
Correct option: (b) 2.0
Explanation:
When the concentration of reactant is reduced to half its initial value, the rate is reduced by 2.4 /0.6 = 4 times
It means, rate ∝ [ reactant]2
So, order of reaction = 2
