Which of the following is an amorphous solid?
a) Graphite
b) Quartx glass
c) Chrome alum
d) Silicon carbide
Answer:
b) Quartx glass
Explanation:
It is composed of particles with irregular shapes, and there is no long-range order in the particles of the amorphous solid.
Crystalline solids
- Intermolecular forces are uniformly distributed throughout the crystalline solids, allowing them to maintain their regular ordered arrays of constituents.
- Crystalline solids are distinguished by their sharp edges and faces, the ability to refract x-rays, and the tendency to have high melting temperatures.
Amorphous solids
- Amorphous solids are solids that do not have a well-defined interior structure. Rubber, plastic, and gels are all examples of amorphous solids, as is amorphous glass.
- Amorphous solids crumble into irregular fragments with irregular edges when they are broken.
The difference between a crystalline and an amorphous solid is as follows:
The following table summarises the differences between crystalline and amorphous solids.
| Properties | Crystalline solid | Amorphous solid |
| Structure | The constituent particles, atoms, ions, or molecules are arranged in regular and definite three-dimensional patterns. For example, sodium chloride, diamond, sugar, etc. | The constituent particles are arranged in irregular three-dimensional patterns. |
| Cutting with a knife | Gives clean, sharp cleavage. | Unclean cleavage. |
| Compressibility | Rigid and incompressible | Usually rigid and can not be compressed to any appreciable extent. |
| Melting point | They have a sharp and definite melting point. | The melting point is not definite. Melt over a range of temperatures. |
| Heat of fusion | Definite | Not definite. |
| Physical properties | These are anisotropic in that their physical properties are not identical in all directions. | These are isotropic, that is their physical properties are identical in all directions. |