When a liquid is heated, which of the following best describes what happens to its particles?

• A. The particles move slower and the liquid evaporates.
• B. The particles stop moving and the liquid solidifies.
• C. The particles move faster and the temperature of the liquid increases.
• D. The particles slow down and the temperature of the liquid decreases.

Answer: (C)

Verified step by step guidance

1. Understand that heating a liquid means adding thermal energy to it, which affects the motion of its particles.
2. Recall that temperature is a measure of the average kinetic energy of particles; when temperature increases, particles move faster.
3. Recognize that as particles gain energy from heating, they vibrate and move more rapidly, increasing the temperature of the liquid.
4. Note that evaporation occurs when particles at the surface gain enough energy to escape into the gas phase, but this is a separate process from the general increase in particle speed due to heating.
5. Conclude that the best description is that the particles move faster and the temperature of the liquid increases when it is heated.