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Question
What makes a glass different from a solid such as quartz? Under what conditions could quartz be converted into glass?
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Solution
- Quartz is a hard and crystalline mineral composed of mainly silicon and oxygen atoms. These atoms exist in a continuous link framework of SiO4 tetrahedra.
- Each oxygen is being shared between two units of SiO4.
- Quartz is considered to be the second most abundant mineral in Earth’s crust after feldspar.
- On the other hand, glass is considered to be a non-crystalline and often amorphous solid. It has a widespread practical, technological and decorative use in various fields.
- Glass is often formed by the rapid cooling of the molten form; few glasses, such as volcanic glass, are naturally occurring.
- However, glass on a commercial basis is prepared from silica or silicon dioxide.
- When we compare the two solids, we see that quartz is a crystalline solid with relatively long-range order and glass is an amorphous solid with short-range order and has a tendency to flow.
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