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Question
Which of the following is an amorphous solid?
Options
Graphite (C)
Quartz glass (SiO2)
Chrome alum
Silicon carbide (SiC)
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Solution
Quartz glass (SiO2)
Explanation:
| Crystalline Silica (Quartz) | Amorphous Silica (Glass) | |
| 1. | Crystalline in nature. Also called quartz. | Light white powder. |
| 2. | All four corners of \[\ce{SiO4}\] tetrahedron are shared by others to give a network solid. | The \[\ce{sio4}\] tetrahedron are randomly joined giving rise to polymeric chains, sheets or three- dimensional units |
| 3. | High and sharp melting point (1710°C) | Does not have sharp melting point. On heating softens gradually to liquid. |
(a) Crystalline (Quartz)
(b) Amorphous (Quartz glass)
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