UPSC Combined Geo-Scientist
Chemist
- 3 descriptive papers
- 200 marks each
- 3 h per paper
Mains Paper III covers analytical and organic chemistry.
All years
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Mains Paper III, analytical and organic chemistry
Question paper, 2020
UPSC Combined Geo-Scientist, Stage II (Mains). 8 pages, as issued by UPSC.
Every question of 2020, one page each51 parts in 10 questions, with the question as text and the key points of its answer
Question 1 40 marks
- 1(a)Significant figures5 marks
- 1(b)Particle diameter in chromatography5 marks
- 1(c)NDIR determination of carbon monoxide5 marks
- 1(d)Thermobalance5 marks
- 1(e)Matrix effects in XRF5 marks
- 1(f)Sample introduction into ICP5 marks
- 1(g)Formation of excited calcium atoms5 marks
- 1(h)Spectrophotometric chromium in a mineral5 marks
Question 2 30 marks
Question 3 30 marks
Question 4 30 marks
Question 5 30 marks
Question 6 40 marks
- 6(a)Dichlorocarbene ring expansion4 marks
- 6(b)Anionic polymerisation of substituted styrenes4 marks
- 6(c)Cyanohydrin formation and hydrolysis4 marks
- 6(d)Doebner condensation4 marks
- 6(e)Hydration with skeletal rearrangement4 marks
- 6(f)Diene reactivity in Diels–Alder reactions4 marks
- 6(g)Norrish II reactivity4 marks
- 6(h)UV maximum of a dienone4 marks
- 6(i)Carbonyl stretching frequencies4 marks
- 6(j)Distinguishing three carbonyl compounds by proton NMR4 marks
Question 7 30 marks
Question 8 30 marks
Question 9 30 marks