VKC ScienceChemistry for written exams Telegram

Indian Forest Service (Mains)

Chemistry optional

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

Paper I covers physical and inorganic chemistry.

Indian Forest Service (Mains), Chemistry optional · 2023 · Paper I

Q2(b). NO and the nitrosonium ion

Question

Draw the molecular orbital diagram of NO molecule. Predict the magnetic behaviour and bond order. Comment on the stability of NO⁺ ion.

Answer in brief

NO has bond order 2.5 and one unpaired electron. Removing its antibonding electron gives diamagnetic NO⁺ with bond order 3 and a stronger, shorter N–O bond.

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 2023 solution2023 question paper

Topic notes: molecular orbital theory: LCAO, MO diagrams of N₂, O₂, CO, NO, CN⁻ and HF, bond order and magnetism, with every Civil Services, IFoS and Geo-Scientist PYQ →

CoversMO diagram of NOnitrosonium ion NO⁺bond orderparamagnetismmolecular orbital theory

All parts of Question 2