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Question
Under which situations can an amorphous substance change to crystalline form?
Solution
| Property | Crystalline solids | Amorphous solids |
| Shape Melting point | Definite characteristic geometrical shape Melt at a sharp and characteristic temperature | Irregular shape Gradually soften over a range of temperature |
| Cleavage property | When cut with a sharp edged tool. they split into two pieces and the newly generated surfaces are plain and smooth | When cut with a sharp edged tool. they cut into two pieces with irregular surfaces |
| Heat of fusion | They have a definite and characteristic enthalpy of fusion | They do not have definite enthalpy of fusion |
| Anisotropy Nature Order in arrangement of constituent particles | Anisotropic in nature True solids Long range order |
Isotropic in nature Pseudo solids or super cooled liquids Only short range order |
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