Question

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 1

Hint: We know that the change of one or more substances into other substances having different composition and properties is called a chemical reaction. Reactions that absorb energy are endothermic. Further on the basis of our characterization we will select the endothermic reaction amongst the given options.

Complete answer:
As we know, the chemical reaction in which the energy is stored in the form of heat is known as an endothermic reaction, whereas an exothermic reaction is known as a chemical reaction in which energy is emitted or evolves in the form of heat. The key distinction in these terms lies, however, in the type of energy that is used or emitted during every chemical reaction. Simply stated, endothermic reactions consume energy in the form of heat from the atmosphere. An exothermic response, on the other hand, releases energy into the system's surroundings. Whenever the energy used to split the bonds between the molecules is higher than the energy given out when bonds are formed in the products, an endothermic reaction takes place. Chemical reactions in which the reactants absorb heat energy from the surroundings to form products are called endothermic reactions.
Endothermic reactions are unit chemical reactions whereby energy from the surroundings is absorbed by the reactants to create products. The temperature of their surrounding region is lowered by these reactions, inflicting a cooling impact. In general, endothermic reactions embrace the formation of chemical bonds by heat absorption from the atmosphere. Decomposition of carbonate is an example of thermal decomposition and reaction is: \[CaC{{O}_{3}}\to CaO+C{{O}_{2}}\]
At \[1200K,\] carbonate decomposes to administer carbon dioxide and quicklime. Once heated, carbonate decomposes into calcium oxide and carbon dioxide. This method is utilized within the production of fast lime, which is a very important substance in several industries.
Therefore, the correct answer is option D.

Note:
Remember that the exothermic reaction causes the reaction mixture and its surroundings to become hotter. While endothermic reaction causes the reaction mixture and its surroundings to become colder.