A characteristic feature of a reversible reaction is that:
[A] They never proceed to completion.
[B] They proceed to completion.
[C] They are not complete unless the reactants are removed from the sphere of reaction mixture.
[D] None of the above.

Question

A characteristic feature of a reversible reaction is that:
[A] They never proceed to completion.
[B] They proceed to completion.
[C] They are not complete unless the reactants are removed from the sphere of reaction mixture.
[D] None of the above.

Vedantu Content Team · Accepted Answer

HINT: A reaction where the reactants and the products are in equilibrium with each other is known as a reversible reaction. It means that reactants and the products can be interconverted. Weak acids and bases undergo reversible reactions.COMPLETE STEP BY STEP SOLUTION: We know that the chemical reactions that take place can either be irreversible or irreversible. Let us discuss this first and then try to solve the given question. If we can get back the starting substance after it has undergone a change then the change is reversible and if we get a substance which cannot be reverted back to the original substance then the change is irreversible. In a reversible chemical change, the reactants and the products both are at equilibrium. Once equilibrium is reached, the reaction can move either way. The reactants can change into products and the product can also change back into the reactants.$$aA+bB\rightleftharpoons cC+dD$$ Now for a reversible reaction, the system is in equilibrium with its surrounding. It would take infinite time to complete a perfectly reversible process and thus it will never proceed towards completion. The reactant will be in equilibrium with the product.  It cannot proceed towards completion because both forward reaction and the reverse reaction take place at the same rate and thus maintaining a stable equilibrium. We can understand from the above explanation that a characteristic feature of a reversible reaction is that it will never precede towards completion.Therefore, the correct answer is option [A] they never proceed to completion.NOTE: Before 1803 it was assumed that chemical reactions proceed only in one direction. It was only after 1803 that a French scientist Claude Louis Berthollet observed the formation of sodium carbonate crystals and recognised this as a reverse of a familiar reaction.$$\begin{align} & 2NaCl+CaC{{O}_{3}}\to N{{a}_{2}}C{{O}_{3}}+\to CaC{{l}_{2}} \\ & N{{a}_{2}}C{{O}_{3}}+CaC{{l}_{2}}\to 2NaCl+CaC{{O}_{3}} \\ \end{align}$$

A characteristic feature of a reversible reaction is that:[A] They never proceed to completion.[B] They proceed to completion.[C] They are not complete unless the reactants are removed from the sphere of reaction mixture.[D] None of the above.

A characteristic feature of a reversible reaction is that:
[A] They never proceed to completion.
[B] They proceed to completion.
[C] They are not complete unless the reactants are removed from the sphere of reaction mixture.
[D] None of the above.