UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper II
Q15(b). Rule of mutual exclusion: CO₂ and H₂O
Question
State and explain the ‘rule of mutual exclusion’. Why in H₂O molecule, all the vibrations are IR and Raman active while in CO₂, only some vibrations are IR and some Raman active?
Model answer
The free solution for 2023 answers questions 1, 2, 3, 4, 6, 8, 10, 11, 13 and 14, the ones picked in its time plan. Question 15 is answered in full in the Geo-Scientist Chemistry Paper II, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper II: Model Answers 2021 to 2025
- All fifteen questions of each paper, with the question printed above its answer
- Numericals worked from formula to result with units; graphs with labelled axes
- Topic-wise weightage and a topic-wise index
Coversrule of mutual exclusionIR and Raman activitycentre of symmetryCO2 vibrationsH2O vibrations
All parts of Question 15
- 15(a) Fundamental of DCl from that of HCl (same force constant)10 marks
- 15(b) Rule of mutual exclusion: CO₂ and H₂O10 marks