Indian Forest Service (Mains)
Chemistry optional
- 2 papers
- 200 marks each
- 3 h per paper
Paper I covers physical and inorganic chemistry.
All years
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Paper I, physical and inorganic chemistry
Question paper, 2025
Indian Forest Service (Mains), Chemistry optional. 7 pages, as issued by UPSC.
Every question of 2025, one page each42 parts in 8 questions, with the question as text and the key points of its answer
Question 1 40 marks
Question 2 40 marks
Question 3 40 marks
Question 4 40 marks
- 4(a)(i)Boiling point at reduced atmospheric pressure5 marks
- 4(a)(ii)Chemical potential of supercooled water5 marks
- 4(b)(i)Incongruent melting and azeotropy5 marks
- 4(b)(ii)Testing the stated activity-coefficient result10 marks
- 4(c)(i)Hydrogen and propane fuel cells10 marks
- 4(c)(ii)Competition between zinc deposition and hydrogen5 marks
Question 5 40 marks
Question 6 40 marks
Question 7 40 marks
Question 8 40 marks