Which product is formed when quick lime reacts vigorously with water?

The correct option is Calcium hydroxide.

Explanation

The reaction between quick lime and water is a classic example of a combination reaction, a type of chemical reaction where two or more substances combine to form a single product. This process is characterized by being highly exothermic.

Detailed Analysis:

• Quick lime is the chemical common name for Calcium oxide (CaO).
• When quick lime reacts vigorously with water, it produces Calcium hydroxide [Ca(OH)₂].
• This product is commonly referred to as slaked lime.
• The chemical equation governing this reaction is:
  CaO(s) + H₂O(l) → Ca(OH)₂(aq) + Heat
• Calcium carbonate (Limestone) is not formed in this step; rather, it is formed when slaked lime reacts with carbon dioxide in the atmosphere over time.

Key Takeaway: The hydration of Quick lime (Calcium oxide) results in the formation of Slaked lime (Calcium hydroxide) and the release of a significant amount of heat.