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 \(\frac{1}{10}\)th value?
Answer & explanation
Correct answer: option 4
k = 60 s-1, t = ?
If initial concentration is [A0]
Then one tenth of the initial concentration will be \(\frac{[A_o]}{10}\)
Using expression for first order reaction,
t = \(\frac{2.303}{k}\)log\(\frac{[A_o]}{[A]}\)
t = \(\frac{2.303}{60}\)log\(\frac{[A_o]}{[A_o/10]}\)
t = \(\frac{2.303}{60}\)log10
t = 0.0383 s