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Topic Mole concept
Asked 8 times across 4 UPSC exams over 32 years (1994–2026), peaking in 2017.
Key insights
- Most tested in CDS — 3 of 8 PYQs
- Most asked in 2017
- Recurs across 6 years (1994–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CSE 1994 → CDS 2017 → GEO 2022 → NDA 2024
How the concept evolved
Rising — more than half its appearances (7 of 8) are since 2016.
Related concepts
Ideas UPSC tests alongside this one — keep exploring.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
GEO2026
A tablespoon holds 0·5 mole of water. What is the number of molecules present in it?
- A 6·02 × 10^23
- B 3·01 × 10^23
- C 9
- D 36
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
NDA2025
Which one of the following statements is NOT correct?
- A Half mole of nitrogen gas is measured 11.2 litre at STP
- B 17 gram of ammonia gas contains 6.022 × 10^23 molecules at STP
- C 22.4 litre of CO2 gas at STP contains 44 gram of molecules
- D 4 gram of hydrogen gas contains 6.022 × 10^23 molecules ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
NDA2024
The mass of 0.5 mole of N2 gas is
- A 7 g
- B 14 g ✓
- C 21 g
- D 28 g
✓ Correct answer: (B)
Science & Technology › Physics & Chemistry
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