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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 · 2017 · Mains Paper II

Q12(b). HI photolysis

Question

The quantum yield for 2HI → H₂ + I₂ at 250 nm is 2.0. If 3070 J is absorbed, calculate the moles of HI decomposed.

Answer in brief

n_(HI)=1.283×10⁻² mol, taking the stated quantum yield for HI disappearance.

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CoversHI photolysisPhotochemistry

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