1. Dry ice is comprising two oxygen atoms bonded to a single carbon atom.
2. It is colorless, with a sour zesty odor, non-flammable, and slightly acidic.
3. At pressures below 5.13 atm and temperatures below 56.4 C (69.5 F) changes from a solid to a gas with no intervening liquid form, through a process called sublimation.
4. The opposite process is called deposition, where changes from the gas.