Question

Which physical state does not have a surface?

Answer 1

Concept: Physical state of gases.

1. Gases have neither a fixed shape nor a fixed volume. Hence, they do not have fixed boundaries.
2. This is because the spaces between the particles in the gas are not fixed and so the particles are free to move.
3. The presence of high kinetic energy and negligible forces of attraction.
4. The particles of all gas can move at high speeds in all directions.

Therefore gaseous states do not have a surface.