Which of the following best describes what happens in an endothermic reaction?

• A. The temperature of the surroundings increases.
• B. The system absorbs heat from the surroundings.
• C. Energy is converted from heat to light.
• D. The system releases heat to the surroundings.

Answer: (B)

Verified step by step guidance

1. Understand the definition of an endothermic reaction: it is a chemical reaction that absorbs heat energy from its surroundings.
2. Recall that in an endothermic process, the system (the reacting substances) gains heat, which means energy flows into the system.
3. Recognize that because the system absorbs heat, the temperature of the surroundings typically decreases, not increases.
4. Eliminate options that suggest the system releases heat or that energy is converted from heat to light, as these do not describe endothermic reactions.
5. Conclude that the best description is: 'The system absorbs heat from the surroundings.'