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UPSC Combined Geo-Scientist

Chemist

  • 3 descriptive papers
  • 200 marks each
  • 3 h per paper

Mains Paper II covers physical chemistry.

UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper II

Q5. Opposing first-order reactions

Question

For Ak₋₁k₁⇌B, both first order, derive (k₁+k₋₁)t=ln [xₑ/(xₑ-x)], where x is B concentration and xₑ its equilibrium value.

Answer in brief

x=xₑ[1-e^(-(k₁+k₋₁)t)], assuming initially only A is present.

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CoversOpposing first-order reactionsChemical kinetics