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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 · 2024 · Mains Paper II

Q5(a). Order of a gas decomposition from two rates

Question

The rate of decomposition of a gas A was 3.70 in some unit when 10% had reacted and it was 2.60 in the same unit when 25% had undergone decomposition. Calculate the order of the reaction.

Answer in brief

n = 1.94 ≈ 2: the decomposition is second order.

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Coversorder of reactiondifferential methodvan 't Hoff methodrate lawsecond order reaction

All parts of Question 5