VKC ScienceChemistry for written exams Telegram

UPSC Combined Geo-Scientist

Chemist

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

Mains Paper I covers inorganic chemistry.

UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper I

Q10(b). Praseodymium magnetic moment

Question

Calculate magnetic moment of Pr₂(SO₄)₃·8H₂O and compare it with spin-only value. Justify the observed deviation. (Atomic number of Pr is 59)

Answer in brief

Each Pr(III) ion has free-ion moment 3.58μ_B, compared with the spin-only value 2.83μ_B.

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 2020 solution2020 question paper

CoversPraseodymium magnetic momentLanthanide magnetism

All parts of Question 10