Question

Describe the factors on which the density of a substance depends.

Answer 1

Some of the factors which influence the density of a substance are discussed here.

1. Physical states of matter: We know that matter is made up of atoms and molecules.
2. On the basis of the arrangement of these atoms in a substance, we classify the physical state of matter as solids, liquids, and gases.
3. Temperature: The density of any substance depends directly on its mass and volume.
4. If any of the two factors changes then the density of the substance also changes.
5. In the case of liquids and gases, there is a large change in their volumes even with small changes in temperature. As a result, when a liquid or a gas is heated, its density decreases, and when cooled, its density increases.
6. Solids do not undergo significant expansion or contraction with a change in their temperature. As a result, there is no significant change in the volume of a solid when it is heated or cooled. So, there is almost no change in its density.
7. Pressure: Solids have a tightly packed structure and hence are incompressible.
8. Thus, the change in the pressure of a solid will not have any effect on its density. On the other hand, At a constant temperature, if the pressure increases, the atoms of the gas come closer and there is a decrease in the volume. So its density will change.