Which of the following reactions is an endothermic  reaction?  

(a) Burning of coal.  

(b) Decomposition of vegetable matter into compost.  

(c) Process of respiration.  

(d) Decomposition of calcium carbonate to form quicklime and carbon dioxide.  

 

Answer

Here,

  • Endothermic Reaction: Endo means in and thermic means heat. In these reactions, heat is absorbed.
  • Exothermic Reaction: Exo means out and thermic means heat. In these reactions, heat is released.

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Endothermic vs Exothermic Reaction-01.jpg

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Let’s look at the reactions one by one

  1. The burning of coal is a combustion reaction in which heat is released. Therefore, it is an exothermic reaction .
  2. Decomposition of vegetable matter also leads to the production of heat, so it is an exothermic reaction .
  3. Respiration is the breakdown of food to release energy. Therefore, it is an exothermic reaction .
  4. Heat is needed to be supplied for the decomposition of calcium carbonate to form quicklime and CO 2 , so it is an endothermic reaction .


So, the correct answer is (d)

  1. Class 10
  2. Chapter 1 Class 10 - Chemical Reactions and Equations (Term 1)

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About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo