Which of the following best describes what happens when a solid melts?

• A. The solid turns directly into a gas without becoming a liquid.
• B. The solid undergoes a chemical reaction and forms a new substance.
• C. The solid changes into a liquid as its particles gain enough energy to move past each other.
• D. The solid loses energy and becomes colder.

Answer: (C)

Verified step by step guidance

1. Understand the process of melting: Melting is a physical change where a solid turns into a liquid when it gains enough energy.
2. Recall that during melting, the particles in the solid gain kinetic energy, which allows them to overcome the fixed positions they held in the solid state.
3. Recognize that melting does not involve a chemical reaction; the substance remains the same chemically, only its physical state changes.
4. Note that melting does not involve the solid turning directly into a gas (which is called sublimation), nor does it involve the solid losing energy and becoming colder.
5. Therefore, the best description is that the solid changes into a liquid as its particles gain enough energy to move past each other.