It consists of platinum wire sealed in a glass tube has platinum foil attached to it. The foil is coated ch finely divided platinum and acts as platinum cathode. It is dipped into an acid solution containing H+. s in 1M concentrated HCl. Pure hydrogen gas is obled into the solution at constant temperature of 298 The surface of the foil acts as a site for the reaction.
standard hydrogen electrode works as anode:
H2(g) → 2H+ + 2e-
standard hydrogen electrode works as cathode:
2H++ 2e- → H2 (g)
The electrode potential of an electrode can be ermined by connecting its half cell with a standard hydrogen electrode.
