Example Question #1 : Solids, Liquids, And Gases
Molecules are constantly moving. In which state of matter do molecules move the fastest?
Molecules move at the same rate in both gases and liquids
Molecules move at the same rate in all three states of matter
The movement of particles is important in differentiating the states of matter. Solids have the lowest molecular energy; their molecules barely vibrate and are generally trapped in lattice structures. Molecules in liquids are able to move more freely, resulting in the fluidity of the liquid state. Gas molecules have even more freedom of movement, allowing the gas to expand to fill a space.
Consider that energy (such as heat) must be added to convert a solid to a liquid or a liquid to a gas. That energy goes to make the molecules move faster and increase the temperature of the compound. Gases require the most energy (consider boiling water), and will have the fastest moving molecules.