CBSE
Class 10
Class 12
Depending upon the nature of bonds, crystalline solids are of four types.
Property of covalent solids
Constituent particles | Major binding force | Properties | Example |
Atoms | Covalent bonds | Very hard, high melting point, high heat of fusion, insulator | Quartz, diamond etc. Exception is graphite |
Property of ionic solids
Constituent particles | Major binding force | Properties | Example |
Positive and negative ions | Electrostatic forces of attraction | Brittle, high melting point, very higt heat of fusion | NaCl, MgO, ZnS, LiF, etc |
Property of Metallic solids
Constituent particles | Major binding force | Properties | Example |
Positive ions and mobile electrons | Metallic bonds | Very soft to very hard, ductile and malleable, conductors | All metals and alloys |
Property of molecular solids
Constituent particles | Major binding force | Properties | Example |
Small molecules | Vander Waal's forces | Soft, low Melting Point, volatile, Insulators. | Solid CO2, wax, Iodine, etc |