How does potentiometry work?

Potentiometry is a way to measure the amount of a specific ion in a solution by checking the voltage between two special electrodes.

Here’s how it works in simple terms:

1. Two electrodes are used:
   • One is a reference electrode, which has a stable, known voltage.
   • The other is an ion-sensitive electrode, which reacts to the specific ion you want to measure.
2. The electrodes are placed in the solution, and a voltmeter measures the difference in voltage between them.
3. The voltage changes depending on the ion concentration: the more of the ion there is, the higher (or lower) the voltage.
4. By comparing the voltage to a standard or calibration, you can figure out the concentration of the ion in the solution.

This method is used in pH meters, water testing, and blood tests.