Assertion (A) Conductivity of all electrolytes decreases on dilution.
Reason(R) On dilution number of ions per unit volume decreases.

Options

A. Both assertion and reason are true and the reason is the correct explanation of assertion.
B. Both assertion and reason are true and reason is not the correct explanation of assertion.
C. Assertion is true but the reason is false.
D. Both assertion and reason are false.

Explanation

### Step-by-Step Solution:

1. **Understanding Conductivity**:
- Conductivity (κ) is a measure of a solution's ability to conduct electricity, which depends on the concentration of ions in the solution.

2. **Effect of Dilution on Electrolytes**:
- When an electrolyte is diluted, the concentration of the ions (cations and anions) in the solution decreases. For example, if we dilute a solution of NaCl, the number of Na⁺ and Cl⁻ ions per unit volume decreases.

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