Correct Answer : Chemical reaction of cement with water
Explanation : As water comes into contact with cement particles, hydration reactions immediately starts at the surface of the particles.
Correct Answer : Option (D) : Aluminum oxide
Explanation : Powder form of aluminum oxide is used for fine polishing process. It is surface treatment process.
Correct Answer : Option (B) : IS 456-2000
Explanation : Option can be eliminated because there is no such code. Maximum nominal size of aggregates to be used in concrete may be as large as possible within the limits prescribed by IS 456:2000.
Correct Answer : Option (C) : 3-4
Explanation : This type of cement was first of all developed in U.S.A. It is recommended that air contents should be 03-04 % by volume.
