Home / Topic / valency
Topic

valency

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

Key insights

  • Most tested in NDA — 2 of 2 PYQs
  • Most asked in 2022
  • Recurs across 1 years (2022–2022)

Across exams

NDA · 2

How the concept evolved

222
Rising — more than half its appearances (2 of 2) are since 2016.

Sample questions

You've seen the pattern — here are a few of the actual PYQs.
NDA2022
Which one of the following is the correct molecular formula of ammonium carbonate if the valency of ammonium ion is (+1) and carbonate anion is (-2)?
  1. A (NH4)2CO3 ✓
  2. B NH4(CO3)2
  3. C (NH3)2CO3
  4. D NH4CO3
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry
NDA2022
Which one of the following is the correct order of the valencies of elements Ne, Si, N and Mg?
  1. A Ne < Mg < N < Si ✓
  2. B Si < N < Mg < Ne
  3. C Ne < N < Si < Mg
  4. D Mg < Ne < N < Si
✓ Correct answer: (A)
Science & Technology › Physics & Chemistry

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