At equilibrium in a thistle funnel experiment

Options

A. No movement of water across the egg membrane take place
B. No net movement of water across the membrane take place
C. No movement of solute across the egg membrane
D. 2 and 3

Answer

To solve the question regarding the equilibrium in a thistle funnel experiment, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Thistle Funnel Experiment**:
The thistle funnel experiment is designed to demonstrate osmosis, where water moves through a selectively permeable membrane (like an egg membrane) from a region of lower solute concentration to a region of higher solute concentration until equilibrium is reached.

2. **Identify the Concept of Equilibrium**:
At equilibrium, the concentration of solute on both sides of the membrane becomes equal, which means that there is no net movement of water or solute across the membrane.

3. **Analyze the Options**:
- **Option 1**: No movement of water across the egg membrane takes place.
- **Option 2**: No net movement of water across the membrane takes place.
- **Option 3**: No movement of solute across the egg membrane.
- **Option 4**: Options 2 and 3.

4. **Evaluate Each Option**:
- **Option 1** is incorrect because while there may be no net movement, there can still be movement in both directions.
- **Option 2** is correct because at equilibrium, the rate of water entering and leaving the solution is equal, resulting in no net movement.
- **Option 3** is also correct because at equilibrium, the concentration of solute is equal on both sides, meaning there is no movement of solute.
- **Option 4** is correct as it combines the correctness of options 2 and 3.

5. **Conclusion**:
The best answer is **Option 4**: No net movement of water across the membrane takes place, and no movement of solute across the egg membrane.

### Final Answer:
**Option 4: 2 and 3**