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Topic Phase equilibrium
Asked 2 times across 2 UPSC exams over 6 years (2020–2026), peaking in 2020.
Key insights
- Most tested in CAPF — 1 of 2 PYQs
- Most asked in 2020
- Recurs across 2 years (2020–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CAPF 2020 → CDS 2026
How the concept evolved
Rising — more than half its appearances (2 of 2) 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.
CDS2026
Which one of the following gives the triple point of water ?
- A Temperature 273·16 K and Pressure 1 Pa
- B Temperature 273·16 K and Pressure 6·11 × 10⁻³ Pa
- C Temperature 0 K and Pressure 10² Pa
- D Temperature 373 K and Pressure 6·11 × 10⁻³ Pa
Answer key not yet available (pending official release)
Science & Technology › Physics & Chemistry
CAPF2020
At triple point the substance co-exists in
- Liquid phase
- Solid phase
- Vapour phase
Select the correct answer using the code given below:
- A 1 only
- B 1 and 2 only
- C 2 and 3 only
- D 1, 2 and 3 ✓
✓ Correct answer: (D)
Science & Technology › Physics & Chemistry
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