Ionisation depends upon

Options

A. Pressure
B. Volume
C. Dilution
D. None of these

Explanation

To solve the question "Ionisation depends upon," we need to analyze the factors that influence the ionization of electrolytes. Here’s a step-by-step breakdown:

### Step 1: Understand Ionization
Ionization refers to the process by which an electrolyte (like an acid or base) dissociates into ions when dissolved in a solvent, typically water. The extent of this ionization can vary based on several factors.

### Step 2: Identify Factors Affecting Ionization
1. **Temperature**: As the temperature increases, the kinetic energy of the molecules also increases, which can lead to a higher degree of ionization. This means that the ionization constant (α) increases with temperature.

2. **Dilution**: When a solution is diluted, the concentration of the ions decreases, which can lead to an increase in the degree of ionization. This is because the ions are less likely to recombine in a more diluted solution.

3. **Pressure and Volume**: For most aqueous solutions, pressure and volume do not significantly affect the ionization of electrolytes. Therefore, these factors can generally be considered irrelevant in this context.

### Step 3: Analyze the Options
- **Option 1: Pressure** - Not a significant factor for ionization in aqueous solutions.
- **Option 2: Volume** - Similar to pressure, volume does not directly affect ionization.
- **Option 3: Dilution** - This is a significant factor that increases the degree of ionization.
- **Option 4: None of these** - This option is incorrect since dilution is indeed a factor.

### Conclusion
Based on the analysis, the correct answer is **Option 3: Dilution**. Ionization depends significantly on dilution and temperature.

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