Plumbic acid, Pb0(OH) 21 is obtained as a bluish-black, lustrous body of electrolysing an alkaline solution of lead sodium tartrate.
By electrolysing an aqueous solution of the chloride with a mercury cathode, a liquid and a solid amalgam, SrHgn, are obtained; the latter on heating gives a mixture of Sr 2 Hg 5 and SrHg 5, and on distillation an amalgam passes over, and not the metal.
The liquors are run off from the vats to the electrolysing baths or precipitating tanks, and the leached ores are removed by means of doors in the sides of the vats into wagons.
Henri Moissan obtained the metal of 99% purity by electrolysing calcium iodide at a low red heat, using a nickel cathode and a graphite anode; he also showed that a more convenient process consisted in heating the iodide with an excess of sodium, forming an amalgam of the product, and removing the sodium by means of absolute alcohol (which has but little action on calcium), and the mercury by distillation.
Davy obtained it by electrolysing caustic soda.