Which of the following is not the property of hydrophilic solutions ?

Options

A. High concentrations of dispersed phase can be easily attained in such sols
B. Coagulation is reversible in these sols
C. Viscosity and Surface tension are about the same as that of water
D. The charge on the hydrophilic sol particle depends on the pH value of the medium, it may be positive, negative or even zero

Answer

To determine which of the following is not a property of hydrophilic solutions, we need to analyze each option provided. Hydrophilic solutions are characterized by their affinity for water, meaning they attract water molecules. Let's go through the properties one by one.

### Step-by-Step Solution:

1. **Understanding Hydrophilic Solutions**:
- Hydrophilic means "water-loving." These solutions attract water molecules and can easily mix with water.

2. **Analyzing the First Property**:
- **High concentration of dispersed phase can be easily attained in such sols**:
- This statement is true. Hydrophilic solutions can maintain a high concentration of dispersed particles due to their affinity for water.

3. **Analyzing the Second Property**:
- **Coagulation is reversible in the sols**:
- This statement is also true. In hydrophilic solutions, coagulation (the process where particles clump together) can often be reversed, allowing the solution to return to its original state.

4. **Analyzing the Third Property**:
- **Viscosity and surface tension are the same as that of water**:
- This statement is not true. While hydrophilic solutions may have properties similar to water, their viscosity and surface tension can differ significantly depending on the nature of the solute and its concentration. Therefore, this is the property that does not apply to hydrophilic solutions.

5. **Analyzing the Fourth Property**:
- **The charge in the hydrophilic sol particle depends upon the pH value of the medium**:
- This statement is true. The charge on hydrophilic particles can vary with the pH of the solution, which can affect their stability and interaction with other particles.

6. **Conclusion**:
- The property that is **not** characteristic of hydrophilic solutions is the third one: **Viscosity and surface tension are the same as that of water**.

### Final Answer:
The property that is not characteristic of hydrophilic solutions is **option number 3**.

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