Q.

The rate constant for a first order reaction is 20 min-1. The time required for the initial concentration of the reactant to reduce to its 132 level is ______ ×10-2 min. (Nearest integer)

(Given: ln 10 = 2.303, log 2 = 0.3010)                                [2023]


Ans.

(17)

t1/2=0.693k=0.69320=0.03465 min

          (12)n=(132)=(12)5

           No. of half-life=5

           Time required=0.03465×5=0.17325 min

            =17.325×10-2 min