Which statement best describes the meaning of mass being conserved during a physical change?

• A. Some mass is lost as energy during the physical change.
• B. The total mass of the substances decreases after the physical change.
• C. The total mass of the substances remains unchanged before and after the physical change.
• D. The mass of each individual substance increases during the physical change.

Answer: (C)

Verified step by step guidance

1. Understand the Law of Conservation of Mass, which states that mass cannot be created or destroyed in a chemical or physical process.
2. Recognize that a physical change involves changes in the state or appearance of a substance without altering its chemical composition.
3. Apply the conservation of mass principle to physical changes, meaning the total mass of all substances before the change must equal the total mass after the change.
4. Evaluate the given statements by comparing them to the conservation of mass principle: mass cannot be lost as energy, nor can it spontaneously increase or decrease during a physical change.
5. Conclude that the correct description is that the total mass of the substances remains unchanged before and after the physical change.