AIIMS 2019 Chemistry Zero Order Reactions MCQ Question

In a zero-order reaction, the half-life (t₁/₂) is given by the equation $t_{1/2} = \frac{[A_0]}{2k}$, where $[A_0]$ is the initial concentration of the reactant and $k$ is the rate constant. When the concentration $[A_0]$ is doubled, the new half-life becomes $t_{1/2}' = \frac{2[A_0]}{2k} = \frac{[A_0]}{k} = 2t_{1/2}$, indicating that the half-life is indeed doubled, thus supporting option B.

Option A is incorrect because the half-life is not halved; option C is also incorrect since the half-life does change with concentration; option D is irrelevant as option B is valid. This illustrates that in zero-order kinetics, the half-life is directly proportional to the initial concentration of the reactant.