Carbon monoxide is a colorless, odorless, tasteless, and extremely poisonous gas. Because it has no odor or color, people breathing it usually fall asleep without realizing they are being poisoned. Carbon monoxide prevents hemoglobin (the oxygen-carrying substance in the blood) from supplying oxygen to the body. Without oxygen, people and animals soon die.
Carbon monoxide is produced when substances containing carbon—such as coal, wood, oil, or gasoline—are oxidized (burned) without enough oxygen present. However, most carbon monoxide in the atmosphere comes from natural sources. For example, the decay of swamp gas and other organic materials in the absence of oxygen produces carbon monoxide. Some reactions in soil and in the atmosphere remove carbon monoxide, thereby keeping the total amount of the gas nearly constant. But car engines also produce carbon monoxide, and dangerous amounts can build up in city streets. United States automakers are required to equip vehicles with devices that convert carbon monoxide to carbon dioxide. Cigarette smoke also has a small amount of carbon monoxide. Even this small quantity can be harmful.
Industry burns carbon monoxide to provide heat for manufacturing processes. The carbon monoxide is usually in a fuel gas such as water gas or producer gas. These gases are sometimes used to heat homes and to cook food (see Gas (How gas is manufactured) ). Carbon monoxide is also used to separate metals such as iron and nickel from their ores and to purify them.
The chemical formula of carbon monoxide is CO. The gas was first prepared in the laboratory in 1776 by J. M. F. de Lassone, a French chemist. Its composition was identified in 1800 by William Cruikshank, an English chemist.
