Question

why burning is considered as chemical change​

Answer 1

Answer:

The process of burning (as opposed to evaporating) is a chemical reaction, a chemical change. The wax molecules are undergoing a chemical change; they are changing into different molecules by reacting with a substance in the air.

Answer 2

Because while burning , the substance goes under oxidation i.e gains oxygen , which is a chemical change …

You can also understand this by… following sentences

If you burn anything , a new substance is formed with totally different properties, which is an observation for chemical change or chemical reaction