Question

If concentration of reactant ‘A’ is increased by 10 times, the rate of reaction becomes 100 times. What is the order of reaction if rate law is rate = k[A]\(^n\)?

• A. 1
• B. 4
• C. 3
• D. 2

Hint:

To determine the order of reaction, compare the change in rate with the change in concentration, and solve for \(n\) using the rate law.

Answer 1

The Correct Option is D

Step 1: Applying the rate law.
For the rate law \( \text{rate} = k[A]^n \), we are told that when the concentration of reactant A is increased by 10 times, the rate of reaction becomes 100 times. This can be written as: \[ \frac{\text{rate}_2}{\text{rate}_1} = \left(\frac{[A_2]}{[A_1]}\right)^n \] Given that \(\frac{\text{rate}_2}{\text{rate}_1} = 100\) and \(\frac{[A_2]}{[A_1]} = 10\), we can solve for \(n\): \[ 100 = 10^n \] \[ n = 2 \]
Step 2: Conclusion.
The order of the reaction is 2.