In the cement the compound quickest to react with water, is

ANS:A - Tricalcium aluminate

Cement has 4 compounds which are known as Bogue compound.

1. Tricalcium silicate: It gives early strength.
2. Dicalcium silicate: It gives ultimate strength.
It also decreases the heat of hydration.

3. Tricalcium Aluminate:it rapidly reacts with.
Water. It is also responsible for the initial setting. It has a high heat of hydration.

4: Tetracalcium Amino Ferrite: It produces less heat. If increase the content reduce the strength slightly.