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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 · 2016 · Paper I

Q5(b)(ii). Lability

Question

Explain the following terms: (ii) Lability

Answer in brief

Lability is kinetic: a labile complex exchanges its ligands rapidly (Taube: substitution half-life under about one minute at room temperature); an inert complex reacts slowly. Octahedral complexes with electrons in eg*, or with fewer than three d electrons, are labile; d³ Cr³⁺ and low-spin d⁴–d⁶ are inert.

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Topic notes: labile and inert complexes, substitution mechanisms, the trans effect, stability constants and the chelate effect, with every Civil Services, IFoS and Geo-Scientist PYQ →

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