Hofmann voltameter is used for determining the chemical composition of water by volume, and the electrochemical equivalent of hydrogen by electrolysis of water. Consists of three vertical glass tubes connected to each other at the bottom, Stopcocks at the top ends of the outside tubes are closed while the inner cylinder is open at the top to allow the addition of water via a reservoir. Platinum electrodes mounted in rubber stoppers are used for the electrolysis of acidified water, for insertion in the open ends of the voltmeter limbs at bottom. Supplied with suitable metallic stand.