Question

which of the following best describes an exothermic reaction? a reaction that absorbs heat energy from its surroundings. a reaction that releases heat energy into its surroundings. a reaction that results in a decrease in temperature. a reaction that creates new energy within a system.

Explanation:

To determine the correct description of an exothermic reaction, we analyze each option:

• The first option describes an endothermic reaction (absorbs heat).
• The second option: Exothermic reactions release heat into the surroundings (e.g., combustion, neutralization).
• The third option: Exothermic reactions usually increase temperature (as they release heat), so a temperature decrease is incorrect.
• The fourth option: Energy cannot be created (Law of Conservation of Energy), so this is invalid.

Answer:

B. A reaction that releases heat energy into its surroundings.