Question

The observations of a study on drug hydrolysis were plotted as the logarithm of the amount of drug remaining (Y-axis) against time (X-axis) and found to be linear. What might be the correct inference?

• A. \( \text{The reaction is zero-order} \)
• B. \( \text{The slope is } 2.303/k \)
• C. \( \text{The units of k are concentration}^{-1} \text{time}^{-1} \)
• D. \( \text{The half-life is } t_{1/2} = 0.693/k \)

Hint:

First-order reactions have a constant half-life, independent of initial concentration.

Answer 1

The Correct Option is D

A linear plot of log drug concentration vs. time suggests a first-order reaction, characterized by: \[ t_{1/2} = \frac{0.693}{k} \] This means the rate of reaction depends on the remaining drug concentration, leading to exponential decay.