Alumina, silica, lime and iron oxide are the basic raw material for the manufacture of Portland cement. The component of Portland cement which first hardens is_____________________?

A. 5CaO. 3 Al2O3
B. 3CaO. Al2O3
C. 3CaO. SiO2
D. 2CaO. SiO2

Leave a Reply

Your email address will not be published.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