Question

which of the following contains physical changes only? (1 point)
color change, melting, evaporation
condensation, dissolving, combustion
melting, boiling, dissolving
evaporation, heat production, color change

Explanation:

Step1: Recall physical - change definition

A physical change is a change in which the substance's chemical composition remains the same. It involves changes in state or appearance.

Step2: Analyze each option

• Option 1: Color change can be a chemical change (e.g., rusting changes color due to chemical reaction), so this option is incorrect.
• Option 2: Combustion is a chemical change as it involves a substance reacting with oxygen to produce new substances, so this option is incorrect.
• Option 3: Melting (solid - to - liquid), boiling (liquid - to - gas), and dissolving (a solute in a solvent) are all physical changes. The chemical identity of the substances does not change.
• Option 4: Heat production can be a sign of a chemical change (e.g., in a combustion reaction), so this option is incorrect.

Answer:

C. melting, boiling, dissolving