Hoffman Electrolysis Apparatus with Platinum and Carbon Electrodes. Platinum Electrodes are used for electrolysis of water and Carbon Electrodes for the electrolysis of of ammonia or hydrochloric acid. For qualitative and quantitative measurement of the effect of electric current on liquid. The glass unit has two connected limbs, graduated to 60ml capacity, integral with reservoir tube and funnel shaped bulb, with a stopcock at the top of each limb. The lower part of the limb accepts the electrodes. Complete with pair of Platinum and Carbon Electrodes.Overall length of glass part 55cm. Without the hardware shown.