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Karnataka Board PUCPUC Science 2nd PUC Class 12

A reaction is second order with respect to a reactant. How is the rate of reaction affected if the concentration of the reactant is reduced to half? - Chemistry

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Question

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

Numerical
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Solution

Rate of reaction, R = k [A]2

If the concentration of the reactant is reduced to half:

If [A] = `1/2` A,

rate = `k (A/2)^2`

= `1/4` kA2

Change in rate of reaction = `(1/4 kA^2) : kA^2`

= `1/4 : 1`

Therefore, the reaction rate decreases to one-fourth its original value.

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Chapter 3: Chemical Kinetics - Exercises [Page 85]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 3 Chemical Kinetics
Exercises | Q 3.6 (ii) | Page 85

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