A heavy white precipitate, consisting of ammonium chloride and columbium nitride, is thrown down, and the ammonium chloride is removed by washing it out with hot water, when the columbium nitride remains as an amorphous residue (Hall and Smith, loc. cit.).
Chemically related to vanadium are the two elements tantalum and columbium or niobium.
Wollaston unsuccessfully endeavoured to show that columbium and tantalum were identical.
In 1809 he proved the elementary character of columbium (niobium) and titanium.
Columbium dioxide, Cb202, is formed when dry potassium columbium oxyfluoride is reduced by sodium (H.
Its double salts with the alkaline fluorides are very important, and serve for the separation of the metal from columbium and titanium.
Three oxides of columbium are certainly known, namely the dioxide, Cb202, the tetroxide, Cb 2 0 4, and the pentoxide, Cb 2 0 5, whilst a fourth oxide, columbium trioxide, Cb203, has been described by E.
In its chemical relationships tantalum is associated with vanadium, columbium and didymium in a sub-group of the periodic classification.
Blomstrand, and others, especially of Marignac, proved the identity of columbium, dianium and niobium, and that ilmenium was a mixture of columbium and tantalum.