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Write the common name and the… (Class 10 Science 2024, Q27)

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ScienceCBSE Class 10 · Board exam 2024, set 31/4/1 · 3 marks · Short answer

CBSE Class 10 Science 2024: question 27

Set in the CBSE Class 10 board exam of 2024, paper 31/4/1, section C, question 27, for 3 marks. Try it first; the hints and our step-by-step solution are below.

Q27 · 3 marks · Short answerChemical Reactions and Equations

Write the common name and the chemical name of the compound . Write the method of its preparation. Give chemical equation for the reaction, when water reacts with .

Source: official question paper from cbse.gov.in (PDF). See it in the full 2024 board paper, set 31/4/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

This compound is used for setting fractured bones.

Hint 2

It is obtained from gypsum, CaSO₄·2H₂O. What must be removed, and at what temperature?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. Common name: Plaster of Paris. Chemical name: calcium sulphate hemihydrate.

    1 mark

  2. Preparation: gypsum is heated at 373 K, and it loses part of its water of crystallisation:

    1 mark

  3. Reaction with water: Plaster of Paris mixed with water sets into a hard mass of gypsum:

    1 mark

Answer: Plaster of Paris; calcium sulphate hemihydrate. It is made by heating gypsum at 373 K.

Where the marks are

  • Common name: Plaster of Paris (½ mark)
  • Chemical name: calcium sulphate hemihydrate (½ mark)
  • Preparation by heating gypsum at 373 K (1 mark)
  • Balanced equation for setting with water to form gypsum (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Chemical Reactions and Equations, one at a time, marked against the answer key and marking points.Back to the full paper2024 board paper, set 31/4/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.