The `Psi_W` of pure water i:s :

Options

A. Minimum
B. Less than DPD
C. Maximum
D. Variable

Answer

**Step-by-Step Solution:**

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

2. **Pure Water Characteristics:** In pure water, there are no solutes present. This means that the concentration of solutes is zero.

3. **Water Potential of Pure Water:** The water potential of pure water is defined as the maximum potential because it has the highest concentration of free water molecules.

4. **Quantifying Water Potential:** The water potential of pure water is considered to be zero (Ψ = 0). This is the reference point for measuring the water potential of solutions with solutes.

5. **Effect of Solutes on Water Potential:** When solutes are added to water, the concentration of free water molecules decreases, which leads to a decrease in water potential. Thus, the presence of solutes results in a negative water potential.

6. **Conclusion:** Therefore, the water potential (Ψ) of pure water is zero, which is the maximum value for water potential.

**Final Answer:** The water potential (Ψ) of pure water is 0.

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