Statement I: Conductivity of all electrolytes decreases on dilution

Statement II: On dilution number of ions per unit volume decreases

Both Statement I and Statement II are correct and Statement II is the correct explanation of Statement I

The correct answer is option 1. Both Statement I and Statement II are correct, and Statement II is the correct explanation of Statement I.

Statement I: Conductivity of all electrolytes decreases on dilution

This statement is generally true. Conductivity is a measure of how well a solution conducts electricity, and it depends on the presence of ions in the solution. When an electrolyte solution is diluted, more solvent (usually water) is added, which reduces the concentration of ions per unit volume. As a result, there are fewer charge carriers available to conduct electricity, leading to a decrease in conductivity. This trend holds for many electrolytes, especially weak electrolytes and non-ideal solutions.

Statement II: On dilution number of ions per unit volume decreases

This statement is also generally true. When an electrolyte solution is diluted, the same number of ions is distributed in a larger volume of solvent. As a result, the concentration of ions per unit volume decreases. This is a direct consequence of dilution and is consistent with the principles of solution chemistry.

Relationship between the statements:

Explanation of Statement I by Statement II: The decrease in the number of ions per unit volume on dilution directly explains why the conductivity decreases. Conductivity depends on the mobility of ions and their concentration. When the solution is diluted, the decreased concentration of ions per unit volume means fewer charge carriers are available to conduct electricity. Thus, the conductivity decreases as a result of the decrease in the number of ions per unit volume.

Both statements independently describe aspects of the behavior of electrolyte solutions upon dilution. Statement II provides a logical explanation for why conductivity decreases upon dilution, as stated in Statement I. Therefore, Statement II supports and explains Statement I.

This relationship highlights the interplay between solution concentration, ion mobility, and conductivity, which are fundamental concepts in solution chemistry and electrolysis.