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
Pages 1 and 2 of 39 
Pages 3 and 4 of 39 
Pages 5 and 6 of 39 
Pages 7 and 8 of 39 
Pages 9 and 10 of 39
Pages 11 and 12 of 39 Pages 13 and 14 of 39 Pages 15 and 16 of 39 Pages 17 and 18 of 39 Pages 19 and 20 of 39 Pages 21 and 22 of 39 Pages 23 and 24 of 39 Pages 25 and 26 of 39 Pages 27 and 28 of 39 Pages 29 and 30 of 39 Pages 31 and 32 of 39 Pages 33 and 34 of 39 Pages 35 and 36 of 39 Pages 37 and 38 of 39 Page 39 of 39 
Mains Paper III, analytical and organic chemistry
Solution, 2021
UPSC Combined Geo-Scientist, Stage II (Mains). 39 pages. Questions 1, 2, 5, 6, 7 and 10 are answered.
Every question of 2021, one page each43 parts in 10 questions, with the question as text and the key points of its answer
Question 1 40 marks
- 1(a)Q-test on four results for cadmium in dust5 marks
- 1(b)Ultimate analysis of coal5 marks
- 1(c)Molar absorptivity from the transmittance5 marks
- 1(d)Gravimetric estimation of zinc in brass5 marks
- 1(e)Requirements of an extracting solvent5 marks
- 1(f)Why the ICP is an important source for emission spectroscopy5 marks
- 1(g)Hollow-cathode lamp: function and working5 marks
- 1(h)Powder X-ray diffraction for identifying solids5 marks
Question 2 30 marks
Question 3 30 marks
Question 4 30 marks
Question 5 30 marks
Question 6 40 marks
- 6(a)Reactivity of four alkenes towards electrophilic addition4 marks
- 6(b)Quaternisation, then Sommelet–Hauser rearrangement4 marks
- 6(c)Woodward–Fieser rules: three dienones4 marks
- 6(d)Carbonyl stretching bands of three lactones4 marks
- 6(e)Epoxidation of cholesterol with a peroxy acid4 marks
- 6(f)Norrish Type II reaction of two aryl alkyl ketones6 marks
- 6(g)Three isomeric esters C₄H₈O₂ from ¹H NMR6 marks
- 6(h)McLafferty rearrangement in a ketone, an acid and an ester6 marks
- 6(i)Stretching frequencies of six single bonds2 marks
Question 7 30 marks
Question 8 30 marks
Question 9 30 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.
Printed copy and Kindle
UPSC Combined Geo-Scientist (Main) Chemistry Paper III: Model Answers 2021 to 2025
The book has all five years of Paper III in one volume, with all ten 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.