The following reaction a → b + c + heat is a(n) _____ reaction.

• A. isothermal
• B. neutral
• C. exothermic
• D. endothermic

Answer: (C)

Verified step by step guidance

1. Identify the type of reaction based on the energy change described. The reaction is given as a → b + c + heat, which means heat is released during the reaction.
2. Recall that when a reaction releases heat to the surroundings, it is called an exothermic reaction. Conversely, if a reaction absorbs heat, it is endothermic.
3. Understand the terms: an isothermal reaction occurs at constant temperature (no net heat change), and a neutral reaction is not a standard term in thermochemistry for heat exchange.
4. Since heat is produced and released in this reaction, it is not isothermal or neutral, and it is not absorbing heat, so it cannot be endothermic.
5. Conclude that the reaction is exothermic because it releases heat as a product.