UPSC Civil Services (Mains)
Chemistry optional
- 2 papers
- 250 marks each
- 3 h per paper
- 5 of 8 questions, Q1 and Q5 compulsory
Paper I covers physical and inorganic chemistry.
All years
Pages 1 and 2 of 59 
Pages 3 and 4 of 59 
Pages 5 and 6 of 59 
Pages 7 and 8 of 59
Pages 9 and 10 of 59 Pages 11 and 12 of 59 Pages 13 and 14 of 59 Pages 15 and 16 of 59 Pages 17 and 18 of 59 Pages 19 and 20 of 59 Pages 21 and 22 of 59 Pages 23 and 24 of 59 Pages 25 and 26 of 59 Pages 27 and 28 of 59 Pages 29 and 30 of 59 Pages 31 and 32 of 59 Pages 33 and 34 of 59 Pages 35 and 36 of 59 Pages 37 and 38 of 59 Pages 39 and 40 of 59 Pages 41 and 42 of 59 Pages 43 and 44 of 59 Pages 45 and 46 of 59 Pages 47 and 48 of 59 Pages 49 and 50 of 59 Pages 51 and 52 of 59 Pages 53 and 54 of 59 Pages 55 and 56 of 59 Pages 57 and 58 of 59 Page 59 of 59 
Paper I, physical and inorganic chemistry
Solution, 2021
UPSC Civil Services (Mains), Chemistry optional. 59 pages. All eight questions are answered.
Every question of 2021, one page each30 parts in 8 questions, with the question as text and the key points of its answer
Question 1 50 marks
Question 2 50 marks
Question 3 50 marks
Question 4 50 marks
Question 5 50 marks
- 5(a)Rate constant and half-life of a zero-order reaction10 marks
- 5(b)Lambert–Beer law: statement and derivation10 marks
- 5(c)Oxidation of haem to hematin, and how the protein prevents it10 marks
- 5(d)Geometrical isomers and stereoisomers of M(AB)b₂c₂10 marks
- 5(e)Completing five reactions of xenon compounds10 marks
Question 6 50 marks
Question 7 50 marks
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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.
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.
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 Civil Services (Main) Chemistry Paper I: Model Answers 2021 to 2025
The book has all five years of Paper I in one volume, with every question printed above its answer, a time plan for each paper, the topic-wise weightage of marks and a topic-wise index.