question_answer

Crystalline solids have sharp melting points. Amorphous solids do not melt at a sharp temperature; rather these have a softening range of temperature. Explain.

Answer:

                All bonds in a crystalline solid are equally strong. When the solid is heated, these bonds ruptured at the same temperature. So crystalline solids have sharp melting points.  On the other hand, all bonds in an amorphous solid are not equally strong. When the solid is heated, weaker bonds break at lower temperatures and the stronger ones at higher temperatures. So the solid first softens and then finally melts, i.e., the amorphous solids do not have sharp melting points.