Final answer:
Pyrolysis is the thermal decomposition of solid fuels to produce vapors, occurring in the absence of oxygen and resulting in various chemical products.
Step-by-step explanation:
The thermal decomposition of solid fuels to produce vapors is known as Pyrolysis. This is a chemical process that involves the transformation of a substance, typically a solid material such as wood or coal, into one or more gases, liquids, or solids through the application of heat in the absence of oxygen.
During pyrolysis, chemical bonds are broken down in the material, resulting in the production of various volatile compounds, char, and ash. It's different from combustion and oxidation because it occurs without oxygen, whereas combustion is the burning of a substance in the presence of oxygen. Oxidation is a broader chemical term that includes any reaction where an element combines with oxygen, leading to the formation of oxides, and sublimation is the phase transition of a substance from solid to gas without passing through the liquid phase.