What is the Difference Between Calomel and Glass Electrode?

The main difference between a calomel electrode and a glass electrode lies in their functions in pH measurements:

• Calomel Electrode: A calomel electrode, also known as a saturated calomel electrode (SCE), is a type of reference electrode. Reference electrodes are used to provide a stable reference point for the measurement of pH. Calomel electrodes contain mercury chloride (HgCl2) bathed in a solution of potassium chloride (KCl). They are sensitive to changes in temperature but provide a stable potential.
• Glass Electrode: A glass electrode, on the other hand, is a non-reference electrode. It is used to measure the pH of a system directly.

In summary, while calomel electrodes are used as reference electrodes to provide a stable reference point for pH measurements, glass electrodes are used to directly measure the pH of a solution.

Comparative Table: Calomel vs Glass Electrode

The main difference between a calomel and a glass electrode lies in their classification as reference or non-reference electrodes and the materials they are made of. Here is a comparison table highlighting the differences:

• Calomel electrode, also known as saturated calomel electrode (SCE), is a type of reference electrode used for pH measurement, cyclic voltammetry, and aqueous electrochemistry.

• Glass electrode, on the other hand, is a non-reference electrode used mainly for pH measurements. It consists of a thin glass bulb containing a fixed concentration of HCl solution, into which a silver-silver chloride sensor is immersed.