Vanadium Dichloride: Tetrachloride Vapour and Hydrogen through a Red-Hot Glass Tube (Roscoe 1913)

Vanadium tetrachloride vapour mixed with dry, pure hydrogen is led through a glass tube at dull red heat. The dichloride grows in the tube as apple-green plates. Result: vanadium dichloride, sealed up in hydrogen in the tube it was made in, ready to be reduced to the metal. Source: Roscoe and Schorlemmer, A Treatise on Chemistry vol. 2 (1913), pp. 932-933 and 915. Not given: rate and amounts. Hydrogen chloride is given off; hydrogen is flammable. Picture drawn by Youblob.