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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 · 2021 · Paper I

Q5(a). Second-order conversion after 60 minutes

Question

A reactant reacts 30% in 30 min. If the reaction follows second-order kinetics, find the rate constant and remaining concentration of the reactant after 60 min.

Answer in brief

For −d[A]/dt = k[A]², k = 1/(70[A]₀) in concentration⁻¹ min⁻¹, and [A]₆₀ = (7/13)[A]₀ = 0.5385[A]₀.

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Topic notes: rate laws, integrated rate equations and half-lives, with every Civil Services, IFoS and Geo-Scientist PYQ →

Coverssecond-order kineticsintegrated rate lawrate constantfraction remaining

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