Carbon dioxide gas is formed from the combination of two elements: carbon and oxygen. It is produced from the combustion of coal or hydrocarbons, the fermentation of liquids and the breathing of humans and animals.
It is found in small proportions in the atmosphere and is assimilated by plants which in turn produce oxygen. Carbon dioxide is a small but important constituent of air. Its typical concentration is about 0.036% or 360 ppm. Exhaled air contains as much as 4% carbon dioxide.
Physical Properties of CO2
- CO2 gas has a slightly irritating odor, is colorless and heavier
- It cannot sustain life.
- It freezes at -78.5 °C to form carbon dioxide snow.
- Liquid density : 1032 kg/m3 · Liquid/gas equivalent: 845
- Depending on temperature and pressure, CO2 is a gas that exists
in a gaseous, liquid or solid state.
- Inert, non flammable
- Taste is neutral.
- Non toxic
- In an aqueous solution it forms carbonic acid, which is too
unstable to be easily isolated.
- Latent heat of vaporization : 571.08 kJ/kg
- Vapor pressure : 58.5 bar
- It will not burn or support combustion.