As a result of osmosis the volume of the concentrated solution:

Options

A. gradually decreases
B. gradually increases
C. suddenly increases
D. none

Answer

**Step-by-Step Solution:**

1. **Understanding Osmosis**: Osmosis is the movement of solvent molecules through a semi-permeable membrane from a region of lower solute concentration (more dilute solution) to a region of higher solute concentration (more concentrated solution).

2. **Setting Up the Scenario**: Imagine a container divided into two parts by a semi-permeable membrane. One side (Solution A) has a lower concentration of solute (more solvent), and the other side (Solution B) has a higher concentration of solute (less solvent).

3. **Movement of Solvent**: During osmosis, solvent molecules will move from Solution A (less concentrated) to Solution B (more concentrated). This movement occurs because the system seeks to equalize the concentration of solute on both sides of the membrane.

4. **Effect on Volume**: As solvent molecules move into the concentrated solution (Solution B), the volume of this solution will gradually increase. Conversely, the volume of the less concentrated solution (Solution A) will decrease as it loses solvent.

5. **Conclusion**: Therefore, as a result of osmosis, the volume of the concentrated solution (Solution B) gradually increases.

6. **Final Answer**: The correct option is B: the volume of the concentrated solution gradually increases.

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