UPSC Combined Geo-Scientist, Mains · 2023 · Mains Paper I
Q3(b). Composition of non-stoichiometric wustite
Question
A sample of Wustite FeₓO contains one Fe(III) for every three Fe(II). Find the value of ‘x’.
Answer in brief
x = 8/9 = 0.8889; the composition is Fe₀.₈₈₈₉O.
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Coverswustite FexOnon-stoichiometrycation vacanciesmetal-deficient defectmixed valence
All parts of Question 3
- 3(a) Normal and inverse spinels15 marks
- 3(b) Composition of non-stoichiometric wustite10 marks
- 3(c) Point defects in crystals5 marks