Question

Name the phase of matter in which the particles have the lowest density.

Answer 1

Gases:

1. The particles of matter are held together by a force acting between them, this force is called the intermolecular force of attraction whereas, the space between the particles of a solid is called intermolecular space.
2. The intermolecular force of attraction between the molecules of a gas is very weak.
3. In gases, the particles are loosely packed and the intermolecular spaces between them are very large.
4. Hence particles move at random in all directions with high velocities.
5. Since the molecules of gas are free to move anywhere, it takes the shape and volume of the container.
6. Example: A balloon seller filling a large number of balloons from a single cylinder of gas.
7. In gases, the number of molecules per unit volume is negligible. Therefore, gases have the lowest density as compared to solids and liquids.

Hence gases have almost negligible density as compared to solids and liquids.