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, 2023
UPSC Combined Geo-Scientist, Stage II (Mains). 6 pages, as issued by UPSC.
Every question of 2023, one page each42 parts in 15 questions, with the question as text and the key points of its answer
Question 1 80 marks
- 1(a)van der Waals equation: meaning of a and b5 marks
- 1(b)Exceptional behaviour of hydrogen and helium5 marks
- 1(c)Unit cell of solid C₆₀ and its carbon atoms5 marks
- 1(d)Planes that diffract: simple cubic, a = 5 Å5 marks
- 1(e)Chemical potential and its link with Gibbs energy5 marks
- 1(f)Debye–Hückel limiting law for γ±5 marks
- 1(g)Activation energy of 2HI → H₂ + I₂5 marks
- 1(h)Best coagulant for the Sb₂S₃ sol5 marks
- 1(i)E° of Na⁺/Na from ΔrH° and ΔrS°5 marks
- 1(j)pH from a calomel–quinhydrone cell5 marks
- 1(k)Degeneracy of the level 6h²/8mL² in a cubic box5 marks
- 1(l)Is Peⁱᵏˣ + Qe⁻ⁱᵏˣ an eigenfunction?5 marks
- 1(m)Zero-point energy in joule and in cm⁻¹5 marks
- 1(n)Microwave activity of SF₆, CO, H₂, H₂O and CO₂5 marks
- 1(o)Stark–Einstein law and the quantum yield5 marks
- 1(p)Decay routes of a photoexcited molecule5 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