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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 · 2023 · Mains Paper I

Q7(a). Mohr’s salt from a permanganate titre

Question

If 25 mL of Mohr’s salt solution requires 15.5 mL of 0.1 M KMnO₄ solution for titration, calculate the amount of Mohr’s salt present in one litre of its solution. [Molar mass of Mohr’s salt is 392 g/mol]

Answer in brief

Mohr’s salt concentration = 0.310 mol L⁻¹ = 121.52 g L⁻¹, assuming the usual sulfuric-acid titration.

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Topic notes: redox titrations, redox indicators and iodometry, with every Civil Services, IFoS and Geo-Scientist PYQ →

CoversMohr's saltKMnO4 titrationpermanganometryferrous ammonium sulfatemolarity vs normality

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