Question

Which of the following is the commonly used reference electrode?

• A. Iron electrode
• B. Platinum electrode
• C. Silver electrode
• D. Standard hydrogen electrode (SHE)

Answer 1

The correct option is D Standard hydrogen electrode (SHE)

The potential of an individual half-cell cannot be measured directly. Only the difference between the two half-cell potentials (emf) can be measured.

If the potential of one half cell is known, then, electrode potential of the other half can be calculated using the cell Emf.

So, an electrode of known electrode potential is needed.
With respect to which, potential of other electrodes are calculated.
A half cell which is choosen to be the reference is termed as reference electrode.
Most commonly used reference electrode is Standard hydrogen electrode. Potential of all other electrodes are measured with respect to this electrode.