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
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Paper I, physical and inorganic chemistry
Question paper, 2021
UPSC Civil Services (Mains), Chemistry optional. 8 pages, as issued by UPSC.
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