UPSC Combined Geo-Scientist
Chemist
- 3 descriptive papers
- 200 marks each
- 3 h per paper
Mains Paper II covers physical chemistry.
All years
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Mains Paper II, physical chemistry
Question paper, 2021
UPSC Combined Geo-Scientist, Stage II (Mains). 8 pages, as issued by UPSC.
Every question of 2021, one page each39 parts in 15 questions, with the question as text and the key points of its answer
Question 1 80 marks
- 1(a)Conditions for ideal behaviour of real gases5 marks
- 1(b)Compressibility factor and Z against P plots5 marks
- 1(c)Formula from corner and face-centre positions5 marks
- 1(d)Crystal systems from the unit-cell constants5 marks
- 1(e)Electrophoretic effect in the Debye–Hückel–Onsager theory5 marks
- 1(f)Activity and activity coefficient: units and magnitudes5 marks
- 1(g)Why a finely powdered adsorbent works better5 marks
- 1(h)Half-life of a first order reaction5 marks
- 1(i)Role of H₃PO₄ in the dichromate titration of Fe²⁺5 marks
- 1(j)Why a voltmeter does not give the EMF5 marks
- 1(k)Well-behaved functions: two tests5 marks
- 1(l)Uncertainty in the velocity of an electron5 marks
- 1(m)Microwave activity of C₂H₂, CH₃Cl, C₆H₆ and CO₂5 marks
- 1(n)Highest vibrational frequency among H₂, D₂ and HD5 marks
- 1(o)Photosensitised reactions5 marks
- 1(p)Energy of one mole of 2500 Å photons5 marks
Question 2 10 marks
Question 3 10 marks
Question 4 10 marks
Question 5 10 marks
Question 6 10 marks
Question 7 10 marks
Question 8 10 marks
Question 9 10 marks
Question 10 10 marks
Question 11 20 marks
Question 12 20 marks
Question 13 20 marks
Question 14 20 marks