UPSC Combined Geo-Scientist, Mains · 2024 · Mains Paper I
Q2(c). Polymorphism in crystals
Question
What is polymorphism in crystals? Give an example.
Answer in brief
Polymorphism is the existence of one chemical substance in more than one crystal structure; CaCO₃ occurs as calcite and aragonite.
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CoverspolymorphismcalcitearagoniteCaCO3 polymorphsallotropy
All parts of Question 2
- 2(a)(i) Fluorite and antifluorite5 marks
- 2(a)(ii) Schottky and Frenkel defects5 marks
- 2(a)(iii) Normal and inverse spinels5 marks
- 2(b)(i) Regular and flattened tetrahedra5 marks
- 2(b)(ii) Two bands in high-spin [CoF₆]³⁻5 marks
- 2(c) Polymorphism in crystals5 marks