UPSC Combined Geo-Scientist
Chemist
- 3 descriptive papers
- 200 marks each
- 3 h per paper
Mains Paper I covers inorganic chemistry.
All years
Mains Paper I, inorganic chemistry
Question paper, 2026
UPSC Combined Geo-Scientist, Stage II (Mains). Every question of the 2026 paper is on its own page, with the question as text.
Every question of 2026, one page each39 parts in 11 questions, with the question as text and the key points of its answer
Question 1 50 marks
- 1(a)Zinc blende and wurtzite: radius-ratio rationale5 marks
- 1(b)Spin-forbidden bands in 4d and 5d complexes5 marks
- 1(c)Phosphate buffer at pH 7.405 marks
- 1(d)Onset of AgCl precipitation5 marks
- 1(e)Iodometry and iodimetry5 marks
- 1(f)Masking agents in the estimation of Ca²⁺5 marks
- 1(g)First-row metal in EAN-obeying organometallics5 marks
- 1(h)Radioactive displacement: ²¹⁰Pb and ²²⁶Ra5 marks
- 1(i)Electronic spectra of Eu³⁺ and Am³⁺ complexes5 marks
- 1(j)Urea required to precipitate Fe³⁺ as Fe(OH)₃5 marks