CaO(s) + H₂O(I) → Ca(OH)₂(aq) + Heat, this reaction is called:  

The Correct answer is Combination Reaction.

Key Points

• A combination reaction is a type of chemical reaction where two or more substances combine to form a single product.
• In the given reaction, CaO (calcium oxide), also known as quicklime, reacts with H₂O (water) to form Ca(OH)₂ (calcium hydroxide), which is commonly known as slaked lime.
• The reaction is highly exothermic as it releases a significant amount of heat.
• The general form of a combination reaction is: A + B → AB.
• In this reaction, CaO (A) combines with H₂O (B) to form Ca(OH)₂ (AB).
• Combination reactions are also called synthesis reactions as they result in the formation of a new compound.
• The product, calcium hydroxide, is an important compound used in various applications such as whitewashing, water treatment, and soil stabilization.

 Additional Information

• Wurtz Fitting Reaction
  • The Wurtz Fitting reaction is a chemical reaction where an aromatic halide reacts with an alkyl halide in the presence of metallic sodium in dry ether to form an aromatic hydrocarbon.
  • This reaction is used for the synthesis of alkylbenzenes.
  • It is different from the given reaction and does not involve the combination of substances to form a single product.
• Decomposition Reaction
  • A decomposition reaction is a chemical reaction where a single compound breaks down into two or more simpler substances.
  • It is the reverse of a combination reaction and often requires the input of energy such as heat, light, or electricity.
  • An example of a decomposition reaction is: 2H₂O → 2H₂ + O₂.
• Wurtz Reaction
  • The Wurtz reaction involves the reaction of an alkyl halide with metallic sodium in dry ether to form a higher alkane.
  • This reaction is used in organic chemistry for the synthesis of alkanes.
  • It is not related to the combination reaction of calcium oxide and water.