Wood is a pure substance. If not, give reasons.

Wood is not a pure substance. It is a complex mixture. Here's why:

Composition: Wood is composed of various substances including cellulose, hemicellulose, lignin, and various organic compounds such as resins and tannins. Each of these components has its own distinct chemical structure.

Variability: The proportion and type of these components can vary depending on the species of tree, the part of the tree, and environmental conditions. This variability means wood is not uniform in composition.

Physical Mixture: Since wood is a mix of different substances physically combined, and not a single chemical compound, it fits the definition of a mixture rather than a pure substance.

In summary, because wood consists of a combination of different chemical compounds and its composition can vary, it is considered a mixture rather than a pure substance.