Question

Give the reaction that occurs at standard hydrogen electrode when it acts as positive electrode in an electrochemical cell.

Answer 1

When the Standard Hydrogen Electrode (SHE) acts as the positive electrode (cathode) in an electrochemical cell, reduction takes place at it. The hydrogen ions from the solution gain electrons and get converted into hydrogen gas.

\[\ce{2H{^+_{(aq)}} + 2e- -> H2_{(g)}}\]