If you heat a gas, what effect will this have on the movement of the particles?
When we heat a substance, its molecules absorb this heat energy and their kinetic energies increase. This results in weakening of bonds holding these particles together and we observe a change of state from solid to liquid. With further heating, the particles attain an even higher amount of kinetic energy and move around faster, thus overcoming the intermolecular bonds. This causes a change of state from liquid to gas phase. These two phenomena are commonly observed as melting and boiling, respectively.
When the substance is in gas phase, the molecules already are away from each other and are able to move around freely. If we heat a gas, heat energy would be imparted to these molecules and upon attaining kinetic energy, they will move faster, causing the gas to be more mobile.
Hope this helps.