Question

How does the standard hydrogen electrodes works?

Answer 1

A standard hydrogen electrode can operate both as an anode and as a cathode.

 When a standard hydrogen electrode is oxidized in a cell, it acts on the anode. During this process, hydrogen is converted into H+ ions, which are converted into solution.

  H2 → 2H+ + 2e–

 When the standard hydrogen electrode is reduced in the cell, it acts as a cathode. During this process, H+ ions from the solution are converted into hydrogen gas.

 2H+ + 2e– → H2

 Thus, the electrode is reversible relative to H+ ions.