NEET Chemistry Chemical Kinetics Questions Solved


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

(A) 0.046 s                                                         

(B) 0.46 s

(C) 1.124 s                                                         

(D) 2.123 s

(A) k=60s-1

Let, initial conc. of the reactant = a

Final conc. of the reactant= 116 × a = a16

For a first order reaction,

t = 2.303k log a a /16 = 2.303 60s-1 log 16 = 0.046 s

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