Question

Which of the following is an example of an exothermic reaction?

• A. \( \text{H}_2 + \text{Cl}_2 \rightarrow 2 \, \text{HCl} \)
• B. \( \text{N}_2 + 3 \, \text{H}_2 \rightarrow 2 \, \text{NH}_3 \)
• C. \( \text{C}_6\text{H}_6 + 15 \, \text{O}_2 \rightarrow 6 \, \text{CO}_2 + 3 \, \text{H}_2\text{O} \)
• D. \( \text{N}_2 + 3 \, \text{H}_2 \rightarrow 2 \, \text{NH}_3 \)

Hint:

Remember: Exothermic reactions release energy, while endothermic reactions absorb energy. Combustion reactions are usually exothermic.

Answer 1

The Correct Option is A

Step 1: Understand exothermic reactions An exothermic reaction is a chemical reaction that releases energy in the form of heat. In exothermic reactions, the products have lower energy than the reactants. Step 2: Identify the exothermic reaction Among the options: - Option (1) is the formation of hydrogen chloride, which is an exothermic reaction. - Option (2) is the formation of ammonia, which is also exothermic. - Option (3) is the combustion of benzene, which is a highly exothermic reaction. Answer: Therefore, option (1) represents an exothermic reaction. So, the correct answer is option (1).