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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

Q3(a). Silver diffraction angles

Question

Ag is fcc with edge 408.6 pm. Find the first two Bragg diffraction angles from (111) planes using wavelength 154.43 pm.

Answer in brief

θ₁=19.11°, θ₂=40.89°; the corresponding measured scattering angles 2θ are 38.21° and 81.78°.

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CoversSilver diffraction anglesX-ray diffraction

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