A. Sand & coke is the main raw material for the manufacture of silicon carbide
B. Carbon refractories cannot be used in the furnaces operating under reducing conditions
C. Mullite can be obtained by the heating of alusite, kyanite or sillimanite
D. Silica occurs in nature in all cellular, amorphous or crystalline form

Leave a Reply

Your email address will not be published. Required fields are marked *