Chemical composition of water by volume and the electrochemical equivalent of hydrogen by electrolysis of water can be demonstrated using this. It is provided with a platinum electrode pair, carbon electrode pair, two stop cocks and a graduated limbs (capacity 50ml).Platinum electrodes can be mounted in rubber stoppers at the base of two limbs for electrolysis of water. After electrolysis hydrogen and oxygen gas will be collected in two limbs at the apex. Carbon electrodes are used for electrolysis of HCl or NH3 solutions. It is fixed on a metal stand. Operatable at 12 V DC, 2.5 Amp.