Question

Velocity constant (k) for a reaction is \(2.3 \times 10^{-5} \, L \, mol^{-1} s^{-1}\). Order of the reaction will be:

Hint:

Always determine reaction order by comparing units of rate constant.

Answer 1

Step 1: Dimensions of k.
- For zero order: unit = mol L\(^{-1}\) s\(^{-1}\).
- For first order: unit = s\(^{-1}\).
- For second order: unit = L mol\(^{-1}\) s\(^{-1}\).
Step 2: Given unit.
Here, \(k = 2.3 \times 10^{-5} \, L mol^{-1} s^{-1}\), which matches second order.
Step 3: Conclusion.
Thus, the reaction is
second order.