In a solid, molecules are held together by strong intermolecular forces of attraction. As a result, they are unable to move from their initial place but they can vibrate at their mean position.
Hence, in solid substances the molecules have low kinetic energy.
Whereas in liquids, the molecules are held by less strong intermolecular forces of attraction as compared to solids. Due to which they are able to slide past each other. Hence, they have medium kinetic energy.
In gases, the molecules are held by weak Vander waal forces. Hence, they have high kinetic energy due to which they move rapidly from one place to another leading to more number of collisions.
Hence, gases are able to expand more rapidly as compared to liquids.
In plasma state, there is hot ionized gas which contains positively charged ions and negatively charged electrons.
In plasma state, molecules move much more rapidly than molecules of a gas.
Thus, we can conclude that solid state of matter has least amount of kinetic energy.
