How do solids and gases change state?
By sublimation: The change from a solid state directly into
 a gas is called sublimation. As the particles of solid dry ice
gain energy their motion completely overcomes the attraction
 between the particles, and the particles escape into the air as gas.

By deposition: is the change in state from

 a gas directly to a solid. Deposition

 is the process by wich ice crystals form in clouds.