What happens to the atoms of the wood when you burn the wood?

Answer 1

When you burn a wood, the volatile gases present in the wood heat up to about 500 degrees Fahrenheit. The compound molecules break apart, followed by the reintegration of the atoms with oxygen, as well as carbon dioxide and other substances. After the burning process, the water in the wood is lost, and the only components that remain are the noncombustible ones, including carbon, potassium, and calcium.

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The wood is destructively distilled. Molecules of cellulose are broken down to carbon, ash, carbon monoxide, methanol, and a variety of larger molecules that are collectively referred to as creosote. The carbon monoxide is burned into carbon dioxide, and the methanol is burned into carbon dioxide and water, as is the creosote, if there is enough oxygen. In the end the carbon can also burn into carbon monoxide and then carbon dioxide. If the combustion is complete, you have ash, carbon dioxide, and water vapor. If the combustion is incomplete you might still have a clean fire that leaves charcoal, but that will happen only if the fire is regulated to produce that result. Unregulated incomplete combustion produces creosote smoke, which can be quite nasty.