Question

A substance having initial concentration (a) reacts according to zero order kinetics. How much time will the reaction take to reach the completion?

• A. $\frac{a}{K}$
• B. $\frac{K}{a}$
• C. $\frac{a}{2K}$
• D. $\frac{2K}{a}$

Answer 1

Answer: (A)

$\frac{a}{K}$

For a zero order reaction, $\left[A_0\right]-\left[A\right]=Kt$

When the reaction is complete, $\left[A\right]=0$.

$\left[A_0\right]-\left[A\right]=\left[A_0\right]-0=\left[A_0\right]=K{t}_{completion}$

$t_{completion}=\frac{\left[A_0\right]}{K}=\frac{a}{K}$