Explanatory notes
… of its elements; white masses with a crystalline fracture, decomposing in the cold on contact with water and … insulator; used for lining electric ovens or for the manufacture of crucibles. Silicon nitride (Si 3 N 4 ) is a … zirconium, vanadium, niobium, tantalum, molybdenum and tungsten borides are obtained by heating mixtures of metal …