Question

Write unit of rate constant for second order reaction.

Hint:

Summary of Linear Equation Solutions: Intersecting lines = Unique solution. Parallel lines = No solution. Coincident lines = Infinite solutions.

Answer 1

Concept:
The unit of rate constant depends on the order of the reaction. Rate law: \[ \text{Rate} = k[A]^n \] Units of rate are: \[ mol\,L^{-1}s^{-1} \]
Second Order Reaction:
For a second order reaction: \[ \text{Rate} = k[A]^2 \]
Unit Calculation:
\[ k = \frac{\text{Rate}}{[A]^2} \] Substitute units: \[ k = \frac{mol\,L^{-1}s^{-1}}{(mol\,L^{-1})^2} \] \[ = L\,mol^{-1}s^{-1} \]
Alternative Form:
\[ M^{-1}s^{-1} \] (where \(M = mol\,L^{-1}\)) \[ \boxed{L\,mol^{-1}\,s^{-1}} \]