The rate constant of a first-order reaction is 10−2 min−1. The half-life period of the reaction is:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 69.3 min
For a first order reaction the half-life depends only on the rate constant, not on the initial concentration:
\( \displaystyle t_{1/2}=\frac{0.693}{k} \)
Substituting k = 10−2 min−1:
\( \displaystyle t_{1/2}=\frac{0.693}{10^{-2}\,\mathrm{min^{-1}}} \)
\( \displaystyle t_{1/2}=69.3\,\mathrm{min} \)