Chemical Kinetics Question 15

Question 15 - 01 February - Shift 2

$A \to B$

The above reaction is of zero order. Half life of this reaction is $50 min$. The time taken for the concentration of $A$ to reduce to one-fourth of its initial value is $\min$.

(Nearest integer)

Show Answer

Answer: (75)

Solution:

Assume reaction starts with 1 mole A

$(t _{1 / 2}=\frac{a}{2 k}, K=\frac{1}{2 \times 50}.$

For $75 %$ completion

$a-\frac{a}{4}=kt$

$t=\frac{3}{4} \frac{a}{k}=\frac{3}{4} \times \frac{100}{a}=75$