UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper II
Q15(b). CO₂ bending mode: IR active, Raman inactive
Question
The bending vibration of linear carbon dioxide is IR active but Raman inactive, though both dipole moment and polarisability change with vibration. Explain with reason.
Model answer
The free solution for 2020 answers questions 1, 2, 3, 4, 5, 7, 8, 11, 12 and 13, the ones picked in its time plan. This part is not answered on the site yet. New answers are announced on Telegram.
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CoversCO2 bending modemutual exclusion ruleIR and Raman activitypolarisability
All parts of Question 15
- 15(a) Rotational constant versus bond length and reduced mass5 marks
- 15(b) CO₂ bending mode: IR active, Raman inactive5 marks
- 15(c) Photodimerisation of anthracene: [A₂] independent of [A]10 marks