Lecture 27 : Experimental methods in chemical kinetics
A sketch of the reaction set up is shown in Fig 27.2
Figure 27.2 The polarimeter set up for the inversion of sucrose.
The role of the nicol prism is to produce two beams of plane polarized light which differ by a phase difference of half wavelength. This allows for an easy detection of plane of polarization at the telescope, where one half of the view is fully bright and the other half, dark.
One of the main advantage of this physical method is that the reactant concentration can be measured without disturbing the system. This is possible because a physical property is used to measure the concentration. In chemical methods, a small part of the reaction mixture is removed, the reaction process stopped (quenched) and the concentration of one or more of the species is measured by a chemical reaction, such as a titration.
