The water potential & osmotic potential of pure water is :

Options

A. 100 & zero
B. Zero & zero
C. 100 & 200
D. Zero & 100

Answer

To answer the question regarding the water potential and osmotic potential of pure water, we can break down the concepts step by step.

### Step-by-Step Solution:

1. **Understanding Water Potential**:
- Water potential (Ψ) is a measure of the potential energy of water in a system and is influenced by the presence of solutes and pressure.
- The formula for water potential is given by:
\[ Ψ = Ψ_s + Ψ_p \]
where Ψ_s is the osmotic potential and Ψ_p is the pressure potential.

2. **Water Potential of Pure Water**:
- In the case of pure water, there are no solutes present. Therefore, the osmotic potential (Ψ_s) is zero.
- Additionally, in an open system (like a beaker of pure water), the pressure potential (Ψ_p) is also zero.
- Thus, the water potential of pure water is:
\[ Ψ = 0 + 0 = 0 \]

3. **Understanding Osmotic Potential**:
- Osmotic potential (Ψ_s) is the potential energy of water due to the presence of solutes. It is always negative or zero.
- Since pure water has no solutes dissolved in it, the osmotic potential is:
\[ Ψ_s = 0 \]

4. **Conclusion**:
- Therefore, both the water potential and osmotic potential of pure water are:
\[ Ψ = 0 \quad \text{and} \quad Ψ_s = 0 \]

### Final Answer:
The water potential and osmotic potential of pure water are both **0**.

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