When you apply heat energy to a substance, which of the following is most likely to occur?

• A. The temperature of the substance increases unless a phase change occurs.
• B. The substance emits light as its primary response.
• C. The substance always undergoes a chemical reaction.
• D. The mass of the substance increases.

Answer: (A)

Verified step by step guidance

1. Understand that when heat energy is applied to a substance, the energy can be used in two main ways: increasing the temperature of the substance or causing a phase change (such as melting or boiling).
2. Recall that temperature increase means the average kinetic energy of the particles in the substance increases, which is the most common initial response to added heat.
3. Recognize that during a phase change, the temperature remains constant because the heat energy is used to break or form intermolecular bonds rather than increasing kinetic energy.
4. Note that emitting light as a primary response or undergoing a chemical reaction are not typical or guaranteed outcomes when heat is applied; these require specific conditions or substances.
5. Understand that the mass of a substance does not increase simply by adding heat, as mass is conserved unless matter is added or removed.