Question

The increase in equivalent conduction of a salt solution on dilution is due to the increase in the:
A. Attraction between the ions
B. Degree of ionization of the salt
C. Molecular attraction
D. Association of the salt

Answer 1

Hint: Think about what happens during conduction and through what medium it takes place. Analyze whether the conductance is dependent on the ions or the molecules, and what conditions would affect the ability of the salt to conduct.

Complete step by step solution:
First let us take into consideration what equivalent conductance actually means. The equivalent conductance defines the conductance of a defined volume of electrolyte which contains one gram equivalent of the salt or the dissolved substance. This solution has to be placed between two parallel electrodes that are 1 cm apart from each other; they should be big enough so that the entire volume of the solution lies between them. Here, conductance means the ability of a solution to conduct electricity.
In the definition of equivalent conductance, we can see the dependence on charged particles or electrons for the conductance of electricity. Thus, we can say that the conductance depends on the ions and not the molecules.
Now, we will determine on what property of the ions does the conductance depend on. Electricity is conducted by the transfer of charged particles, as these particles will increase, the amount of conducted electricity will also increase.
When a solution is diluted, due to reduced attraction between ions as a result of increase in the number of solvent molecules, the degree of ionization will increase. This will cause the formation of more ions that are able to conduct electricity. Thus, an increase in degree of ionization will result in an increase in the equivalent conductivity.

Hence, the correct answer is ‘B. degree of ionization of the salt’

Note: If the ions are attracted to each other, this will inhibit their ability to travel and conduct electricity, attraction between ions will not cause an increase in conductivity. An increase in dilution will decrease the attraction as the number of solvent molecules is increased.