Tritantalum Pentanitride, Ta₃N₅

Tritantalum Pentanitride, Ta₃N₅, has been obtained as a bright red, amorphous powder by passing ammonia over heated tantalum pentachloride. On being heated in air it forms the pentoxide, and when fused with caustic potash it evolves ammonia.

Nitrides of doubtful composition are also formed by the action of ammonia or cyanogen11 on the heated pentoxide. Fusion of a mixture of tantalum pentoxide and carbon in excess of sodium carbonate under ordinary conditions also gives rise to a tantalum-nitrogen product.