JEE Main · 2022 · 29 Jul 2022 · Shift 2 · s-Block Elements

Portland cement contains ' X ' to enhance the setting time. What is ' X '?

(A) $CaSO_{4} \cdot \frac{1}{2} H_{2} O$
(B) $CaSO_{4} \cdot 2 H_{2} O$ ✓ Correct
(C) $CaSO_{4}$
(D) $CaCO_{3}$

Answer: (B)

Solution

Gypsum (

CaSO_{4} \cdot 2 H_{2} O

) is added to Portland cement to control the setting time. It slows down the hydration of tricalcium aluminate, preventing the cement from setting too quickly.

Answer: (B)

CaSO_{4} \cdot 2 H_{2} O

JEE Main · 2022 · 29 Jul 2022 · Shift 2 · Single correct option

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