A solution with osmotic pressure `pi_(1)` is separated from another solution of osmotic pressure `pi_(2)` by SPM solvent flows from `pi_(1) to pi_(2)`, then

Options

A. `pi_(1) > pi_(2)`
B. `pi_(1) lt pi_(2)`
C. Solutions are isotonic
D. Solutions are ideal

Answer

To solve the problem regarding the flow of solvent between two solutions separated by a semi-permeable membrane, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Osmotic Pressure**:
- Osmotic pressure (π) is a measure of the tendency of a solvent to move into a solution through a semi-permeable membrane. It is directly related to the concentration of solute in the solution.

2. **Identifying the Given Information**:
- We have two solutions with osmotic pressures π₁ and π₂.
- The solvent flows from the solution with osmotic pressure π₁ to the solution with osmotic pressure π₂.

3. **Analyzing the Direction of Solvent Flow**:
- According to the principles of osmosis, solvent flows from a region of lower osmotic pressure to a region of higher osmotic pressure.
- Since the solvent is moving from π₁ to π₂, it indicates that π₁ must be less than π₂.

4. **Establishing the Relationship**:
- If π₁ < π₂, it implies that the concentration of solute in the solution with osmotic pressure π₁ is lower than that in the solution with osmotic pressure π₂.
- This means that the solution with osmotic pressure π₁ has a higher concentration of solvent (or lower concentration of solute) compared to the solution with osmotic pressure π₂.

5. **Conclusion**:
- Therefore, we conclude that the correct relationship is π₁ < π₂.

### Final Answer:
The correct answer is: **π₁ is less than π₂**.

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