Chemistry - Chemical Kinetics Question with Solution | TestHub

Question Explanation:

Determine the condition for equal product concentrations in parallel first-order kinetics. Concept: Parallel First-Order Reactions.

Solution:

In a parallel reaction where a single reactant A forms two different products B and C , the rate of formation for each depends on their respective rate constants, ${\mathrm{k}}_1$ and ${\mathrm{k}}_2$.

Calculation:

Rate of formation of B:

$$\frac{d[B]}{dt}=k_1[A]$$

Rate of formation of C:

$$\frac{d[C]}{dt}=k_2[A]$$

Taking the ratio:

$$\frac{d[B]/dt}{d[C]/dt}=\frac{k_1[A]}{k_2[A]}=\frac{k_1}{k_2}$$

For $[B]=[C]$ to be true at all times, the ratio must be equal to 1.

Therefore, the condition is $k_1=k_2$. Final Answer: Option (B)