Question

A first order reaction has a half life period of $69.3sec$. At $0.10molli{t}^{-1}$ reactant concentration rate will be:

• A. ${10}^{-4}Mse{c}^{-1}$
• B. ${10}^{-3}Mse{c}^{-1}$
• C. ${10}^{-1}Mse{c}^{-1}$
• D. $6.93\times {10}^{-1}Mse{c}^{-1}$

Answer 1

The correct option is B ${10}^{-3}Mse{c}^{-1}$

As we know,
$t_{1/2}=69.3sec\therefore k=\frac{0.693}{69.3}={10}^{-2}se{c}^{-1}$

Now, $r=k\left[A\right]={10}^{-2}\times 0.1={10}^{-3}Mse{c}^{-1}$