|MadSci Network: Chemistry|
Fergus, Definitely chemical if you go by a question/definition that I have found works very well: Is the substance(s) destroyed? If yes, then it is a chemical change. The process of burning is combustion and results in the loss of a substance and the gain of another substance (could be carbon if you burned it bad). In this case, you are burning sugars and other substances in the crust, and they are being replaced with other carbon compounds. T. J. Wilkinson
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