Question

The rate constant for a reaction at the initial concentration of $ 2 \times 10^{-2}\, mol\, L^{-1} $ is $ 4 \times 10^{-3}\, mol\, L^{-1}\, min^{-1} $ . The half-life period for this reaction in seconds is

• A. $ 300 $
• B. $ 150 $
• C. $ 180 $
• D. $ 240 $

Answer 1

Answer: (B)

From the unit of rate constant, order of reaction is zero
Hence, $t_{1/2}=\frac{[A]_{0}}{2k}$
$=\frac{2\times 10^{-2}}{2\times4\times 10^{-3}}$ minutes
$=2.5$ minutes
$=150$ seconds