Dry ice is frozen carbon dioxide. It is in solid state but changes to gas phase when it gets heated up. This process of solid being converted to gas instead of liquid is called sublimation. Dry ice sublimates into carbon dioxide gas. As there is no liquid (wet) state involved in this process, it is called ‘dry’ ice. It is much denser and colder than traditional ice.
Dry ice is made from carbon dioxide (CO2). CO2 is compressed with pressure till it liquefies. Then the pressure is released. Now some of the liquid carbon dioxide is transformed into a gas (vaporizes) while some cools down to form dry ice which is further compressed to form cylindrical pellets or blocks.
As it is too cold (-78.5°C), it is very dangerous to touch dry ice with bare hands. Holding dry ice with bare hands would result in freezing the skin and causing severe frostbites within few minutes. It can damage the skin cells and cause serious injury requiring medical attention. It should be handled with insulated gloves. It sublimates faster than the melting of normal ice.