Question

The structure of quartz belongs to which one of the following classes of silicates?

• A. Orthosilicate
• B. Inosilicate
• C. Tectosilicate
• D. Phyllosilicate

Hint:

Silicate classification:
- Tectosilicate: Framework (Quartz, Feldspar).
- Phyllosilicate: Sheet (Micas, Clay).
- Inosilicate: Chain (Pyroxene, Amphibole).
- Nesosilicate: Isolated (Olivine, Garnet).

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
This question tests knowledge of silicate mineral classification based on structure.

Step 2: Detailed Explanation:
Quartz belongs to the tectosilicate (C) class of silicates.
Tectosilicates (framework silicates) have a three-dimensional framework structure.
All four oxygen atoms are shared between tetrahedra.
Examples: Quartz, Feldspar, Zeolites.
Other silicate classes:
- Orthosilicate (A): Nesosilicates (isolated tetrahedra).
- Inosilicate (B): Chain silicates (e.g., Pyroxenes, Amphiboles).
- Phyllosilicate (D): Sheet silicates (e.g., Micas, Clay minerals).
Thus, quartz is a tectosilicate.

Step 3: Final Answer:
Thus, quartz belongs to the tectosilicate class, which corresponds to option (C).
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