An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to:

Options

A. increase in ionic mobility of ions
B. 100% ionization of electrolyte at normal dilution
C. increase in both i.e. number of ions and ionic mobility of ions
D. increase in number of ions

Answer

To solve the question regarding the increase in equivalent conductance of a strong electrolyte with dilution, we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Understanding Equivalent Conductance**:
Equivalent conductance (Λ) is defined as the conductivity (k) of the solution multiplied by the volume (V) of the solution. The formula is:
\[ \Lambda = k \times V \]

2. **Effect of Dilution**:
When a strong electrolyte is diluted, the volume (V) of the solution increases. This means that the concentration of ions in the solution decreases, leading to a lower number of charge carriers per unit volume.

3. **Ionic Mobility**:
With dilution, although the number of ions per unit volume decreases, the mobility of the ions increases. This is because ions have more space to move around, reducing the interactions with other ions and the solvent.

4. **Increase in Equivalent Conductance**:
The increase in ionic mobility contributes to an increase in equivalent conductance. Even though the number of ions per unit volume decreases, the enhanced mobility of the ions compensates for this decrease, resulting in an overall increase in equivalent conductance.

5. **Conclusion**:
Therefore, the main reason for the increase in equivalent conductance of a strong electrolyte with dilution is primarily due to the increase in ionic mobility of the ions.

### Final Answer:
The increase in equivalent conductance of a strong electrolyte with dilution is mainly due to the increase in ionic mobility of ions.

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