For a first order reaction, the rate constant is 2.31 10⁻³ s ⁻¹ . The time required for 75 % completion of the reaction is ________ minutes.

Step-by-step solution

For a first order reaction, the time required for 75 % completion is equal to two half-lives ( 2 t_ 1/2 ). Given rate constant, k = 2.31 10⁻³ s ⁻¹ . The half-life of the reaction is given by: t_ 1/2 = 0.693 k = 0.693 2.31 10⁻³ = 300 s Total time required for 75 % completion = 2 300 s = 600 s . Converting the time into minutes: t = 600 60 minutes = 10 minutes . Answer: 10