|MadSci Network: Chemistry|
No, not exactly, Stephen. Anything that burns is called a fuel. Substances such as these fuels are carbohydrates, made of carbon and hydrate (hydrogen + oxygen) with various other elements attached. Others may be hydrocarbons, which are made of hydrogen and carbon. When carbohydrates or hydrocarbons burn completely in the presence of oxygen, the resulting compounds are carbon dioxide (CO2) and water (H2O), which are both invisible gases.
Smoke is a result of incomplete combustion. Smoke contains tiny particles with the CO2 and H2O which break off from the carbohydrate and are carried with other gases by the heat. Other gases may be from the heat changing the carbohydrate into something else. For example, let's say you have hydrocarbon such as octane (C8H18). It has 8 carbons and 18 hydrogens. If completely burned with oxygen gas around it(O2), it would make 8 carbon dioxide (CO2) molecules and 9 waters (H2O).
C8H18 + 12.5O2 -->
8CO2 + 9H2O or
2C8H18 + 25O2 --> 16CO2 + 18H2O (to make the O2 even)
However, if it were only partially burned, it could break into a number of new compounds such as 2 butanes (C4H10) and other hydrocarbons, or take the oxygen to form alcohols, ketones, and aldehydes. Cigarettes and incense release some of these byproducts that are not totally burned. Ketones and aldehydes have especially strong odors. Also in the cigarette smoke are particle of nicotine, an addictive drug, and tar and other cancer causing chemicals. That's not to say that wood smoke and incense don't have cancer causing chemicals as well. To play it safe, its best not to inhale any type of smoke since you never know what type of incompletely combusted hydrocarbon you may be putting into your lungs.
Hope that helps. Keep on questioning, Stephen!
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