Question

which of the following is not an example of chemical change? sour milk burning wood rust breaking a pencil

Explanation:

A chemical change results in a new substance being formed. Souring milk is a fermentation - a chemical reaction. Burning wood involves combustion, creating new substances like carbon dioxide and ash. Rusting is an oxidation reaction forming iron oxide. Breaking a pencil only changes its physical shape, not its chemical composition.

Answer:

D. breaking a pencil