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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 · 2019 · Mains Paper II

Q9(a). Chain-reaction quantum yield

Question

For H₂ + Cl₂ → 2HCl the quantum yield is 1.0×10⁶ at 480 nm. Find the amount of HCl produced per calorie of radiant energy absorbed.

Answer in brief

16.8 mol HCl per absorbed calorie, taking the quantum yield as HCl molecules formed per absorbed photon.

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CoversChain-reaction quantum yieldPhotochemistry

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