VKC ScienceChemistry for written exams Telegram

UPSC Combined Geo-Scientist

Chemist

  • 3 descriptive papers
  • 200 marks each
  • 3 h per paper

Mains Paper II covers physical chemistry.

UPSC Combined Geo-Scientist, Mains · 2018 · Mains Paper II

Q12(a). Infrared-active molecules

Question

Which may show an infrared vibrational absorption spectrum: Cl₂, HCl, NH₃, CO₂ and CH₄?

Answer in brief

HCl, NH₃, CO₂ and CH₄ have IR-active vibrations; Cl₂ does not have an ordinary electric-dipole fundamental.

Part of VKC Basic

Read the key points and the full model answer with VKC Basic

VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.

See what is included Already a member? Sign in

The full model answer

As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.

The handwritten model answer pages open with the VKC plan.
Read the whole 2018 solution2018 question paper

CoversInfrared-active moleculesVibrational spectroscopy

All parts of Question 12