Which type of reaction is indicated when a fire flares up upon the addition of water?

• A. A neutralization reaction, because acids and bases react.
• B. An endothermic reaction, because heat is absorbed from the surroundings.
• C. A precipitation reaction, because a solid forms.
• D. An exothermic reaction, because heat is released rapidly.

Answer: (D)

Verified step by step guidance

1. Understand the context: When water is added and a fire flares up, it means heat is being released quickly into the surroundings.
2. Recall the definitions of reaction types: An exothermic reaction releases heat, while an endothermic reaction absorbs heat.
3. Analyze the options: Neutralization involves acid-base reactions but does not necessarily cause a fire or rapid heat release; precipitation involves solid formation, not heat release.
4. Connect the observation to the reaction type: The rapid release of heat causing a fire flare-up indicates an exothermic reaction.
5. Conclude that the reaction is exothermic because the heat released upon adding water causes the fire to flare up.