|MadSci Network: Botany|
The major components of wood are lignin and cellulose. These molecules are made of carbon, hydrogen and oxygen, which are chemically combined together. Fire is a chemical reaction in which light and heat are given off. In order to have fire, you need a fuel and an oxidiser. In our atmosphere, oxygen is the most widely used oxidiser. Oxygen combines with the components of wood to release a lot of heat. The light comes from some of the carbon atoms which do not burn fully to carbon dioxide. If you put a spoon over a flame for just a second or two, (do not hold the spoon in the flame for more than this because the spoon conducts heat and you will burn your hand) you will see the black deposits of carbon on the underside.
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