What is a chemical reaction? List an example

A chemical reaction is a process where one or more substances are combined into one or more new substances

Explanation:

Substances are either chemical elements or compounds that can be found on the periodic table. A chemical reaction takes the atoms from the substance and rearranges them into a new substance or compound. In a chemical reaction, the reactants cannot create or destroy any atoms (Law of conservation of Mass).

An example of a chemical reaction can be iron and oxygen to create rust, burning of wood. Wherever there is a chemical change (gas bubbles, precipitate, colour change, temperature change, Light created and change in smell or taste)