Electrolysis of water a small-scale electrolytic cell. It consists of three joined upright cylinders. The inner cylinder is open at the top to allow the addition of water and the electrolyte. A platinum electrode is placed at the bottom of each of the two side cylinders, connected to the positive and negative terminals of a source of electricity. When current is run through the Hofmann voltameter, gaseous oxygen forms at the anode (positive) and gaseous hydrogen at the cathode (negative). Each gas displaces water and collects at the top of the two outer tubes, where it can be drawn off with a stopcock.
Standard hydrogen electrode from the previous one it was given the name 'Standard Hydrogen Electrode'. In summary, The choice of platinum for the hydrogen electrode is due to several factors: The surface of platinum is platinized (i.e., covered with platinum black) to: Other metals can be used for building electrodes with a similar function such as the palladium-hydrogen electrode. Because of the high adsorption activity of the platinized platinum electrode, it's very important to protect electrode surface and solution from the presence of organic substances as well as from atmospheric oxygen. Inorganic ions that can reduce to a lower valency state at the