All Exams Test series for 1 year @ ₹349 only
Question

Which of the following compounds is obtained when gypsum is heated at 373 K?

This question was previously asked in
RRB NTPC 2024 Undergraduate CBT 1 Question Paper (29-Aug-2025) (Shift 1)
The correct answer is

CaSO4.(1/2H2O)

The correct answer is option 2 I.e. CaSO.(1/2H2O).

When gypsum (CaSO₄ · 2H₂O) is heated at 373 K (100°C), it loses water and forms calcium sulfate hemihydrate (CaSO₄ · ½H₂O), commonly known as Plaster of Paris.

Reaction: CaSO₄·2H₂O (gypsum) → CaSO₄·½H₂O (Plaster of Paris) + 1½H₂O (steam)

Was this answer helpful?

Similar Questions

  1. Which of the following statements is correct according to the law of conservation of mass?

  2. Which of the following is formed when carbon dioxide reacts with calcium hydroxide?

  3. Which of the following types of reaction represents formation of slaked lime from calcium oxide and water?

  4. What is used in the preparation of calcium sulphate hemihydrate?

  5. What is used to remove permanent hardness of water?

  6. For preparation of which of the following compounds is the chlor -alkali process used?

  7. Which of the following statements is INCORRECT about Rutherford's model of an atom?

  8. Which of the following is the molecular mass of HNO3?

  9. Which of the following statements is INCORRECT?

  10. Which of the following options represents the product(s) of the reaction given below?

    MnO2 + 4HCl →

     


Important Questions from Acids, Bases & Salts

  1. Name the gas used in preparation of bleaching powder.
  2. Which of the following statements is correct according to the law of conservation of mass?

  3. Which of the following is formed when carbon dioxide reacts with calcium hydroxide?

  4. Which of the following types of reaction represents formation of slaked lime from calcium oxide and water?

  5. Which of the following has a pH value of 7?

Need Expert Advice?
Upcoming Exams
RRB Technician
October 06, 2026
RRB JE
October 27, 2026
RRB ALP
November 03, 2026
Test Series
RRB ALP img
Railways
RRB ALP 2026 Mock Test series
1035 Tests 1 Tests Free
1080 Attempts
4.3(238)
English, Hindi

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App