Vanadium Trioxide: the Pentoxide Reduced with Carbon at Red Heat (Thorpe, 1913)

Vanadium trioxide, a black powder, made by heating vanadium pentoxide with carbon to a red heat. It is the oxide Gin reduced with ferro-silicon to make ferro-vanadium. Hot trioxide takes up oxygen quickly and turns back to the dioxide, so it is kept out of the air while hot. Source: T. E. Thorpe, Dictionary of Applied Chemistry vol. V (1913), p. 610. Picture: the book's text.