| S.No | Solid | Liquid | Gas |
| 1. | Solids have fixed shape and definite volume | Liquids have fixed volume but no definite shape. | Gases have no fixed volume and shape. |
| 2. | Solids have high density | Liquids have high density but less than solids | Gases have low density. |
| 3. | Solids show only slight expansion on heating. | Liquids show slight expansion on heating but more than solids. | Gases expand considerably on heating. |
| 4. | They have slight or no compressibility. | They have slight compressibility but more than solids. | They have high compressibility. |
| 5. | Solids do not flow. | Liquids generally flow easily. | Gases flow freely. |
| 6. | They have their melting and boiling points above room temperature. | They have their melting point below room temperature. | They have their melting and boiling points both below room temperature. |
| 7. | Intermolecular forces are very strong and constituent particles are closely packed. | Intermolecular forces are strong enough to keep the particles together but not strong enough to keep them in fixed positions. | Intermolecular forces are very weak and the particles are free to move. |
