Question

If the unit of the rate constant is \( \text{mol} \, (\text{dm}^{-3} \text{s}^{-1}) \), the order of the reaction would be ____________.

• A. zero
• B. 1
• C. 2
• D. 3

Hint:

The unit of the rate constant changes with reaction order and follows the formula: \[ \text{mol}^{1-n} \, \text{dm}^{3(n-1)} \, \text{s}^{-1}. \]

Answer 1

The Correct Option is A

The unit of the rate constant for a reaction of order \( n \) is given by: \[ k = \left( \text{mol}^{1-n} \, \text{dm}^{3(n-1)} \, \text{s}^{-1} \right) \] For a zero-order reaction: \[ k = \text{mol} \, \text{dm}^{-3} \text{s}^{-1} \] which matches the given unit. Thus, the correct answer is zero.