Question

The rate of a first order reaction is $1.8\times {10}^{-3}mol{L}^{-1}mi{n}^{-1},$ when the initial concentration is 0.3 mol $L^{-1}$ . The rate constant in the units of second is

• A. ${10}^{-2}{s}^{-1}$
• B. ${10}^{-4}{s}^{-1}$
• C. $6\times {10}^{-2}{s}^{-1}$
• D. $6\times {10}^2{s}^{-1}$

Answer 1

The correct option is B ${10}^{-4}{s}^{-1}$

$Rate=k\left[C\right]1.8\times {10}^{-3}=k\left(0.3\right)or,k=\frac{1.8\times {10}^{-3}}{0.3}=6\times {10}^{-3}mi{n}^{-1}=\frac{6\times {10}^{-3}}{60}={10}^{-4}{s}^{-1}$