Question

The unit of rate constant for reactions of second order is:

• A. mol L\(^{-1}\) s\(^{-1}\)
• B. L mol\(^{-1}\) s\(^{-1}\)
• C. L mol s\(^{-1}\)
• D. s\(^{-1}\)

Hint:

Order \(n\) rate constant unit \(= \text{L}^{n-1}\text{mol}^{1-n}\text{s}^{-1}\).

Answer 1

The Correct Option is B

Step 1: For second order reaction: \[ \text{Rate} = k[A]^2 \]
Step 2: Units: \[ k = \frac{\text{mol L}^{-1}\text{s}^{-1}}{(\text{mol L}^{-1})^2} = \text{L mol}^{-1}\text{s}^{-1} \]