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Karnataka Board PUCPUC Science 2nd PUC Class 12

The rate constant for a first order reaction is 60 s−1. How much time will it take to reduce the initial concentration of the reactant to its 116th value? - Chemistry

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Question

The rate constant for a first order reaction is 60 s−1. How much time will it take to reduce the initial concentration of the reactant to its `1/16`th value?

Numerical
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Solution

t = `2.303/k log_10  ([A]_0)/([A])`

= `2.303/60 log_10  ([A]_0)/(1/16 xx [A]_0)`

= 0.3838 log10 (16)

= 0.3838 × 1.2041

= 4.62 × 10−2 s

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Chapter 3: Chemical Kinetics - Exercises [Page 87]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 3 Chemical Kinetics
Exercises | Q 3.16 | Page 87

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