The following data is obtained during the first order thermal decomposition of $2 \mathrm{~A}(g) \longrightarrow \mathrm{B}(g)+\mathrm{C}(\mathrm{s})$ at constant volume and temperature.

The rate constant in $\min ^{-1}$ is

• Correct answer
  A

  $0.0693$
• B

  $6.93$
• C

  $0.00693$
• D

  $69.3$

Solution

$2 p-x+x+x=300$ (given) $2 p+x=300$ $\therefore \quad \mathrm{x}=300-200=100$ $\mathrm{k}=\frac{2.303}{10} \log \frac{200}{100}$ $=0.0693 \mathrm{~min}^{-1}$

Hence, the correct answer is option: 'A'.