Volatile Organic Compounds or VOCs, in chemistry, means the molecule contains carbon. These may be the product when combustion is incomplete or the carbon’s in the fuel cannot get all the way to CO2, which may happen if there is not enough oxygen.  We call this phenomena incomplete combustion and carbon monoxide is also a product of this. In addition to combustion, VOCs are also any organic compound that can volatilize (enter the gas-phase from a solid or a liquid) at room temperature and pressure. There are hundreds of compounds that qualify as VOCs. One way to identify VOCs is through smell. For example gasoline vapors, cleaning supplies, paints, bacon sizzling in a pan, plants, and perfume are all VOCs.  Another term commonly used for VOCs is hydrocarbons. 

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