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Topic

Water of crystallization

Asked 3 times in NDA over 2 years (2020–2022), peaking in 2020.
3
PYQs
1
Exams
3
Years active
2020–2022
Span
2020
Peak
3/3
Answers
📅 Full chronological timeline →

Key insights

  • Most tested in NDA — 3 of 3 PYQs
  • Most asked in 2020
  • Recurs across 3 years (2020–2022)

Across exams

NDA · 3

How the concept evolved

120
121
122
Rising — more than half its appearances (3 of 3) are since 2016.

Sample questions

You've seen the pattern — here are a few of the actual PYQs.
NDA2022
Which one of the following salts does not possess water of crystallization?
  1. A Potassium permanganate ✓
  2. B Blue vitriol
  3. C Washing soda
  4. D Mohr's salt
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
NDA2021
What is the number of water molecules present in a Ferrous Sulphate crystal ?
  1. A 1
  2. B 3
  3. C 5
  4. D 7 ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2020
Number of molecules of water of crystallization in copper sulphate, sodium carbonate and Gypsum are
  1. A 5, 10 and 2 respectively
  2. B 10, 2 and 5 respectively
  3. C 5, 2 and 10 respectively ✓
  4. D 2, 5 and 10 respectively
✓ Correct answer: (C)
Science & Technology › Physics & Chemistry

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