Question

The reaction $\text{CaC}{{\text{O}}_{3(\text{s})}}\text{ }\rightleftharpoons \text{ Ca}{{\text{O}}_{\left( \text{s} \right)}}\text{ + }{{\text{O}}_{2(\text{g})}}$ goes to completion in the lime kiln because:
A. of the high temperature
B. $\text{CaO}$ is more stable than $\text{CaC}{{\text{O}}_{3}}$
C. $\text{CaO}$ is not dissociated
D. $\text{C}{{\text{O}}_{2}}$ escapes continuously

Answer 1

Hint: For this question, we have to study the process of calcination and about lime kiln where this reaction takes place. The reaction will be affected, if the vessel is open or closed and we will be able to choose the correct answer.

Complete step by step answer:
- In the given question, we have to choose the option about the consequences of reaction which will take place.
- As we know that calcium carbonate is a common dietary supplementary to overcome the deficiency of the calcium in the body.
- When calcium carbonate is decomposed it yields solid calcium oxide and carbon dioxide which is gas.
- Now, the lime kiln is a chamber which is completely insulated and in which the required temperature can be raised.
- The lime kiln is usually used for the calcination of the quick lime or calcium carbonate to form the lime.
- So, when the calcium carbonate is burned in the lime kiln which is an open vessel the conversion of calcium carbonate into calcium oxide takes place.
$\text{CaC}{{\text{O}}_{3(\text{s})}}\text{ }\rightleftharpoons \text{ Ca}{{\text{O}}_{\left( \text{s} \right)}}\text{ + }{{\text{O}}_{2(\text{g})}}$

- Whereas the carbon dioxide that is formed escapes continuously as it is a gas and reaction proceeds only in the forward direction and not in the backward direction.
So, the correct answer is “Option D”.

Note: The reaction does not go in the back because there is no carbon dioxide left for combining with the calcium oxide. Also, if the vessel will be closed the state of the equilibrium will be obtained instead of the completion of the reaction.