Question

The rate constant of a reaction is $ K = 3.28 \times 10^{-4} \, \text{s}^{-1} $. Find the order of the reaction.

• A. Zero order
• B. First order
• C. Second order
• D. Third order

Hint:

The unit of the rate constant can help determine the order of the reaction. For \( K = 3.28 \times 10^{-4} \, \text{s}^{-1} \), the reaction is first-order.

Answer 1

The Correct Option is B

Step 1: Understand the units of the rate constant.
The rate constant \( K \) has different units depending on the order of the reaction.
For a reaction of order \( n \), the units of \( K \) are: Zero order: \( \text{mol} \cdot \text{L}^{-1} \cdot \text{s}^{-1} \)
First order: \( \text{s}^{-1} \)
Second order: \( \text{L} \cdot \text{mol}^{-1} \cdot \text{s}^{-1} \)

Step 2: Identify the order of the reaction. The rate constant has the units of \( \text{s}^{-1} \), which corresponds to a first-order reaction.