Q2(b). Structures of non-stoichiometric hydrides and oxides
What should be the possible structure of binary hydrides and oxides of the following according to the composition ranges provided in brackets? (i) LuHₓ (1.85–2.23) (ii) ErHₓ (2.82–3.0) (iii) TiOₓ (0.7–1.25) (iv) VOₓ (0.9–1.20) (v) TiOₓ (1.9–2.0)
Model answer
The free solution for 2025 answers questions 1, 3, 4, 6, 9 and 10, the ones picked in its time plan. Question 2 is answered in full in the Geo-Scientist Chemistry Paper I, 2021 to 2025 book, with every part of every paper.
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UPSC Combined Geo-Scientist (Main) Chemistry Paper I: Model Answers 2021 to 2025
- All eleven questions of each paper, with the question printed above its answer
- Titration, gravimetric and nuclear numericals worked with units; structures drawn
- Topic-wise weightage and a topic-wise index
Coversnon-stoichiometric compoundsmetal hydridesfluorite structurerock salt structurerutileTiO
All parts of Question 2
- 2(a) Local ion displacement in BaTiO₃; electrical behaviour15 marks
- 2(b) Structures of non-stoichiometric hydrides and oxides10 marks
- 2(c) Synthesis of YBa₂Cu₃O₇5 marks