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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?
Solution 1
The arrangement of the constituent particles makes glass different from quartz. In glass, the constituent particles have short range order, but in quartz, the constituent particles have both long range and short range orders.
Quartz can be converted into glass by heating and then cooling it rapidly.
Solution 2
Glass is made up of Si04 tetrahedral units. These constituent particles have short range order only. Quartz is also made up of Si04 tetrahedral units. On heating it softens and melts over a wide range of temperature. It is a crystalline solid having long-range ordered structure. It has a sharp melting point. Quartz can be converted into glass by first melting and then rapidly cooling it.
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