Sublimation

Sublimation is a cool science trick. Most solids melt into liquids before turning into gas. But some solids skip the liquid step. They go right from solid to gas. This is called sublimation.

Dry Ice

Dry ice is the best example of sublimation. It is frozen carbon dioxide, and it is very cold. At room temperature, dry ice turns straight into gas. The thick white fog you see is the gas mixing with the air. Dry ice is used to keep food cold and make spooky effects.

Other Examples

Regular ice can sublimate very slowly in a freezer. That is why old ice cubes shrink and get smaller. Snow can also disappear this way on sunny, windy days. Mothballs in a closet slowly sublimate to keep bugs away. Even some air fresheners work by sublimation.

Fun Facts

• Dry ice is about negative 109 degrees Fahrenheit.
• Never touch dry ice with bare hands, it can hurt your skin.
• The word sublimation comes from Latin and means 'to lift up.'

Did You Know?

Comets in space have tails because their icy surfaces sublimate when they get close to the Sun.