Standard Hydrogen Electrode - Practice Questions & MCQ

A hydrogen electrode in which pressure of hydrogen gas is maintained at 1 atm and the concentration of H⁺ ions in the solution is 1M, is called a standard hydrogen electrode (SHE).
SHE half reaction Electrode potential
$\mathrm{H}_2 \rightarrow 2 \mathrm{H}^{+}+2 \mathrm{e}^{-} \quad 0.0 \mathrm{~V}$ (Anode)
$2 \mathrm{H}^{+}+2 \mathrm{e}^{-} \rightarrow \mathrm{H}_2 \quad 0.0 \mathrm{~V}$ (Cathode)

• The emf of a standard hydrogen electrode is taken as 0.00 V at all temperatures.
• It is a reversible electrode.
• It is used as a primary reference electrode.
• Potentials of other species can be calculated by conducting a cell with SHE as one of the electrodes and then calculating the potential difference by various methods.