Carbon dioxide has many applications based on its varied properties. It is widely used in food processing for freezing, cooling, preservation or pH control. It is also used to blanket chemicals, control pH in water treatment, shield metal welding, stimulate biological growth, improve oil and gas production and as a fire-extinguishing agent.
Carbon dioxide is a slightly toxic, odorless, colorless gas with a slightly pungent, acidic taste. It will not burn or support combustion. It is 1.52 times heavier than air and is very soluble in water, forming carbonic acid. Solid carbon dioxide (dry ice) will sublime at atmospheric pressure and -109°F to gaseous carbon dioxide.
Carbon dioxide is formed naturally through fermentation. It is also produced as a by-product of many industrial processes such as ammonia, hydrogen, ethylene oxide, natural gas production and combustion processes.