Question

For a first order reaction,

\[\ce{A -> products}\], initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for the reaction in min⁻¹ is ______.

Options

• 0.9212

• 0.4606

• 0.2303

• 1.3818

Answer 1

For a first order reaction,

\[\ce{A -> products}\], initial concentration of A is 0.1 M, which becomes 0.001 M after 5 minutes. Rate constant for the reaction in min⁻¹ is 0.9212.

Explanation:

Given: Initial concentration of A is 0.1 M,

Final concentration of A is 0.001 M,

Time (t) = 5 min

For first-order reaction:

k = `2.303/t log ([A]_0/[A])`

k = `2.303/5 log(0.1/0.001)`

= `2.303/5 log (100)`

= `2.303/5 xx 2`

= `4.606/5`

= 0.9212 min⁻¹