Q14 of 35 Page 1

The rate constant for a first order reaction is 60 s-1. How much time will it take to reduce 1g of the reactant to 0.0625 g?

Given: Rate constant (k) = 60 s-1


Mass of reactant at intial time (R0) = 1g


Mass of reactant after time t (R)= 0.0625g


We apply the formula:


t = log


⇒ t = log


⇒ t = 0.0462 s


Thus, the time to reduce 1g of the reactant to 0.0625 g is 0.0462s


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