UPSC Combined Geo-Scientist
Chemist
- 3 descriptive papers
- 200 marks each
- 3 h per paper
Mains Paper II covers physical chemistry.
All years
Pages 1 and 2 of 36 
Pages 3 and 4 of 36 
Pages 5 and 6 of 36 
Pages 7 and 8 of 36 
Pages 9 and 10 of 36 
Pages 11 and 12 of 36 
Pages 13 and 14 of 36 
Pages 15 and 16 of 36 
Pages 17 and 18 of 36
Pages 19 and 20 of 36 Pages 21 and 22 of 36 Pages 23 and 24 of 36 Pages 25 and 26 of 36 Pages 27 and 28 of 36 Pages 29 and 30 of 36 Pages 31 and 32 of 36 Pages 33 and 34 of 36 Pages 35 and 36 of 36 
Mains Paper II, physical chemistry
Solution, 2023
UPSC Combined Geo-Scientist, Stage II (Mains). 36 pages. Questions 1, 2, 3, 4, 6, 8, 10, 11, 13 and 14 are answered.
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
Part of VKC Basic
Read the full model answer to every question of this paper with VKC Basic
VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Model answer pages open with the VKC plan.
Printed copy and Kindle
UPSC Combined Geo-Scientist (Main) Chemistry Paper II: Model Answers 2021 to 2025
The book has all five years of Paper II in one volume, with all fifteen questions of every paper answered, the question printed above each answer, a time plan for each paper, the topic-wise weightage of marks and a topic-wise index.