Question

The term infinite dilution refers to when:
A) $\alpha \to 1$, for weak electrolytes
B) An electrolyte is $100\% $ dissociated
C) All interionic effect disappears
D) All of the above

Answer 1

Hint: Infinite dilution can be defined as the term in which a solution contains so much solvent that if one adds more solvent to it there will be no change in the concentration of the solution. One can use this approach to better analyze the options given to get the correct answer.

Complete step by step answer:
1) As per the definition of infinite dilution the concentration of the solution doesn’t change even if there is an addition of the more solvent.
2) This means, at infinite dilution of the weak electrolyte dissociates like a strong electrolyte. This will result in the complete ionization of electrolytes. Hence, the degree of dissociation will be $1$ i.e. $\alpha \to 1$.
3) Therefore, the solution will be $100\% $ ionized and there will be no change even after the addition of any amount of solvent.
4) At the infinite dilution, the ions in an electrolytic solution are placed far apart from each other which nullifies the interionic effect and makes it zero.
5) This will result in the equivalent conductance of an electrolyte solution to become constant, where the number of ions of that electrolyte reaches the maximum capacity and gives constant value.
Therefore, all the above options are proved correct which shows option D as the correct choice.

Note:
The concept of infinite dilution is used in the chemistry to analyze the substance’s dissolution nature in solvents. Infinite dilution is a hypothetical state of the solution where solute concentration is considered to be zero. The degree of dissociation is also called the degree of ionization which is denoted by $\alpha $.