Water potential of a solution is

Options

A. Zero
B. Positive
C. Zero or positive
D. Negative

Answer

### Step-by-Step Solution:

1. **Understanding Water Potential**:
- Water potential is a measure of the potential energy of water in a system and is represented by the symbol Ψ (psi). It determines the direction of water movement and is influenced by solute concentration and pressure.

2. **Pure Water Potential**:
- The water potential of pure water at standard temperature and pressure is defined as zero (Ψ = 0). This serves as a reference point for measuring the water potential of solutions.

3. **Effect of Solute on Water Potential**:
- When a solute is dissolved in water, it decreases the concentration of free water molecules. This results in a decrease in kinetic energy and thus lowers the water potential of the solution.

4. **Calculating Water Potential of a Solution**:
- The water potential of a solution (Ψ) is always less than that of pure water. Therefore, when solute is added to water, the water potential becomes negative.

5. **Conclusion**:
- Since the water potential of a solution is less than zero due to the presence of solute, the correct answer to the question "Water potential of a solution is" is negative.

### Final Answer:
The water potential of a solution is negative.

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