Question

Represent a standard hydrogen electrode.

Answer 1

A platinised platinum foil is in contact with pure hydrogen gas at 1 atmosphere pressure in a solution of H⁺ (more accurately, H₃O⁺) ions at a concentration of 1 mol L⁻¹ to create a standard hydrogen electrode. Consequently, a typical hydrogen electrode can be shown as:

\[\ce{Pt H2_{(g)} (1 atm) | H+ (1 mol L^{-1})}\]