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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 · 2024 · Paper I

Q2(c). Arrhenius parameters from a logarithmic law

Question

The first-order decomposition of ethylene oxide into CH₄ and CO follows log k (s⁻¹) = 14.34 − (1.25 × 10⁴ K)/T. Calculate (i) activation energy, (ii) rate constant at 700 K and (iii) frequency factor A.

Answer in brief

Eₐ = 239.3 kJ/mol, k(700 K) = 3.04 × 10⁻⁴ s⁻¹ and A = 2.19 × 10¹⁴ s⁻¹.

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CoversArrhenius equationactivation energyfrequency factorethylene oxide decompositionfirst-order rate constant

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