Answer :
The main combustible part of wood is cellulose, a compound of carbon, hydrogen, and oxygen, which, when it burns, breaks down to carbon dioxide, water, and heat.
What is Combustible Substance ?
The substances which catches fires easily in air and produce heat and light upon burning is known as Combustible Substances.
Example: Wood, Oil, Kerosene, Hydrogen gas, Cloth etc.
When these compounds carbon, hydrogen and oxygen burns completely the carbon oxidizes to carbon dioxide , water and heat.
Thus from the above conclusion we can say that The main combustible part of wood is cellulose, a compound of carbon, hydrogen, and oxygen, which, when it burns, breaks down to carbon dioxide, water, and heat.
Learn more about the Combustible Substance here: https://brainly.com/question/12875341
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