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UPSC Combined Geo-Scientist

Chemist

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

Mains Paper III covers analytical and organic chemistry.

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

Q4(b). Sodium oxide in feldspar

Question

A 0.5140-g feldspar gives 0.0812 g mixed NaCl/KCl and 0.1450 g K₂PtCl₆. Calculate Na₂O percentage using formula masses K₂PtCl₆ 485.95, KCl 75.5, NaCl 58.5 and Na₂O 62.

Answer in brief

Using the explicitly supplied formula masses, Na₂O = 3.73% by mass.

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CoversSodium oxide in feldsparGravimetric analysis

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