There are many possible routes to determine the rate of a particular reaction in the lab. Any analytical technique which can provide information on the changing concentration of either the reactants or products at varying time intervals can be used to determine reaction rates. Some commonly encountered methods include:

• UV-vis spectroscopy (including Stopped Flow)

• NMR spectroscopy

• Gas chromatography

• High Performance Liquid Chromatography

And many other techniques may be used. However, by far the most commonly used route is UV-vis spectroscopy.

The use of UV-vis measurements to monitor the changes of concentration of either reactants or products (or potentially both) is a routinely used method for the determination of rates for reactions. The Beer-Lambert relationship between absorbance and concentration allows the concentration of a chemical to be easy determined, and through repeated photometric measurements the change in concentration over time can be easily measured.

In the laboratory, most kinetic runs are recorded under pseudo-first order reaction conditions, where the rate of a reaction is determined by monitoring the change of a single component. More information regarding this approach can be found in the background theory pages.