Which of the following has highest surface tension ?

Options

A. Water
B. Soap solution in water
C. Detergent solution in water
D. Glycerol in water

Explanation

To determine which of the given options has the highest surface tension, we will analyze each option based on the solubility of the substances in water and their effects on surface tension.

### Step-by-Step Solution:

1. **Understanding Surface Tension**:
- Surface tension is a property of liquids that describes the elastic-like force existing at the surface of a liquid. It is influenced by the intermolecular forces between the molecules in the liquid.

2. **Analyzing the Options**:
- The options provided are:
1. Water
2. Soap solution in water
3. Detergent solution in water
4. Glycerol in water

3. **Surface Tension of Water**:
- Water is a pure substance with strong hydrogen bonding between its molecules. This results in relatively high surface tension compared to many other liquids.

4. **Surface Tension of Soap Solution**:
- Soap is sparingly soluble in water. When soap is added to water, it disrupts the hydrogen bonding between water molecules, leading to a decrease in surface tension.

5. **Surface Tension of Detergent Solution**:
- Similar to soap, detergents are also sparingly soluble in water. They also disrupt the hydrogen bonds between water molecules, resulting in lower surface tension.

6. **Surface Tension of Glycerol in Water**:
- Glycerol (C3H8O3) is a molecular compound that can form hydrogen bonds with water. When glycerol is dissolved in water, it enhances the hydrogen bonding network, which increases the surface tension of the solution.

7. **Comparison of Surface Tension**:
- Based on the analysis:
- Water has high surface tension.
- Soap solution has lower surface tension due to sparingly soluble soap.
- Detergent solution also has lower surface tension due to sparingly soluble detergent.
- Glycerol in water increases surface tension due to hydrogen bonding.

8. **Conclusion**:
- Among the given options, glycerol in water will have the highest surface tension because it enhances the hydrogen bonding in the solution.

### Final Answer:
**Glycerol in water has the highest surface tension among the given options.**