Determine the order of the reaction given the rate constant K = 5.5 x 10⁻¹⁴ s⁻¹.

The given rate constant is $K = 5.5 \times 10^{-14} \text{ s}^{-1}$. The unit of the rate constant is $\text{s}^{-1}$.

For an $n$-th order reaction, the general units of the rate constant $K$ are given by:

If concentration is in $\text{mol L}^{-1}$ and time is in seconds ($\text{s}$), then:

We are given that the units of $K$ are $\text{s}^{-1}$.
Comparing this with $(\text{mol L}^{-1})^{1-n} \text{ s}^{-1}$, we can see that the concentration term $(\text{mol L}^{-1})^{1-n}$ must be equal to 1. This happens when the exponent $(1-n)$ is 0.

Since $n=1$, the reaction is a first-order reaction.

The order of the reaction is first order.