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, 2021
UPSC Combined Geo-Scientist, Stage II (Mains). 36 pages. Questions 1, 2, 3, 4, 6, 7, 10, 12, 14 and 15 are answered.
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
Part of VKC Basic
Read the full model answer to every question of this paper with VKC Basic
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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.