## Chemistry: Molecular Approach (4th Edition)

The unit of $k$ is : a) $s^{-1}$ - first order reaction b) $M^{-1}s^{-1}$ - second order reaction c) $M.s^{-1}$ - zeroth order reaction
We know that the unit of the rate of the reaction is $Ms^{-1}$, and the unit of $[A]$ is $M$. In a first order reaction: rate of reaction = $k$$[A] So, the unit of k is : s^{-1} In a second order reaction: rate of reaction = k$$[A]^2$ So, the unit of $k$ is : $M^{-1}s^{-1}$ In a zeroth order reaction: rate of reaction = $k$ So, the unit of $k$ is : $Ms^{-1}$