Question

Gypsum is added to clinker during cement manufacturing to:

• A. Decrease the rate of setting of cement
• B. Bind the particles of calcium silicate
• C. Facilitate the formation of colloidal gel
• D. All of the above

Answer 1

The correct option is A Decrease the rate of setting of cement

During the cement manufacturing process, upon the cooling of the clinker, a small amount of gypsum is introduced during the final grinding process. Gypsum is added to control the setting of cement.

If not added, the cement will set immediately after mixing water leaving no time for concrete placing. Hence, the addition of gypsum is required to decrease the rate of setting.

Hence, option $\left(A\right)$ is correct.