Thorium Carbide, ThC₂

Thorium Carbide, ThC₂, was first obtained impure by Troost, who heated thoria with carbon in an electric furnace in order to obtain the metal. This compound was prepared in the pure state, however, by Moissan and Etard, who heated in the electric furnace a mixture of 72 grams of thoria and 6 grams of carbon compressed into small cylinders. The current employed was of 900 amperes at 50 volts, and the operation lasted four minutes. The product, examined under the microscope, consisted of yellow, transparent crystals mixed with graphite; the density of the carbide at 18° C. is 8.96; it burns brilliantly when slightly heated in oxygen, and also forms a sulphide, with beautiful incandescence, when heated in sulphur vapour. Concentrated acids have little action on the carbide, dilute acids attack it rapidly, and water reacts with it readily, yielding a mixture of hydrogen with methane, ethane, propane, butane, ethylene, propylene and homologues, and acetylenic hydrocarbons.