Concept:The rate of a reaction is measured by tracking a physical property that changes linearly as the reaction proceeds. For ions, electrical mobility is the key property.
Solution:- Ions in a solution are responsible for carrying electrical charge.
- If a reaction involves a net change in the number of ions or a change in the type of ions (and therefore their individual mobilities), the overall electrical conductivity of the solution will change as the reaction proceeds.
- This change in conductivity can be continuously measured using a conductivity meter to determine the reaction rate.
Why other options are incorrect:Refractometry is for changes in refractive index (usually organic liquids). Optical rotation is for optically active chiral substances. Dilatometry measures volume changes.
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