Question

which option is an example of a physical change? gasoline burning silver tarnishing iron rusting metal denting

Explanation:

Step1: Define physical change

A physical change is a change in which the form or appearance of matter changes, but not its chemical composition.

Step2: Analyze gasoline burning

Gasoline burning is a chemical reaction where gasoline reacts with oxygen to form new substances like carbon - dioxide and water. So it's a chemical change.

Step3: Analyze silver tarnishing

Silver tarnishing occurs when silver reacts with sulfur - containing substances in the air to form silver sulfide. It's a chemical change.

Step4: Analyze iron rusting

Iron rusting is the reaction of iron with oxygen and water to form iron oxide. It's a chemical change.

Step5: Analyze metal denting

When metal is dented, only its shape changes. The chemical composition of the metal remains the same. So it's a physical change.

Answer:

D. metal denting