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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 · 2025 · Paper I

Q5(e). Reactions in nonaqueous media

Question

Predict the products: (i) PbI₂ and KNH₂ in liquid NH₃; (ii) NaClO₄ and TlF in anhydrous HF; (iii) sucrose with concentrated H₂SO₄; (iv) KI and SOCl₂ in liquid SO₂.

Answer in brief

The reactions illustrate imide formation, salt metathesis, dehydration and halide exchange, respectively.

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Topic notes: non-aqueous solvents: liquid ammonia, HF, sulfuric acid, SO₂, BrF₃ and superacids, with every Civil Services, IFoS and Geo-Scientist PYQ →

Coversliquid ammonia reactionsanhydrous HFliquid SO₂ solventnon-aqueous solventsdehydration of sucrose

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