A dialysis tubing bag containing a 0.5 M sucrose solution is placed in each of the following beakers. In which beaker will osmosis cause the bag to expand?

• A. Beaker A: contains pure water
• B. Beaker B: contains 0.5 M sucrose solution
• C. Beaker D: contains 0.5 M NaCl solution
• D. Beaker C: contains 1.0 M sucrose solution

Answer: (A)

Verified step by step guidance

1. Understand that osmosis is the movement of water across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.
2. Identify the solute concentration inside the dialysis bag, which is 0.5 M sucrose, and compare it to the solute concentration in each beaker.
3. Note that Beaker A contains pure water (0 M solute), so water will move into the bag because the bag has a higher solute concentration, causing it to expand.
4. For Beaker B, which contains 0.5 M sucrose, the solute concentration is equal inside and outside the bag, so there will be no net movement of water and no expansion.
5. For Beaker C (1.0 M sucrose) and Beaker D (0.5 M NaCl, which dissociates into ions increasing total solute concentration), the external solute concentration is higher than inside the bag, so water will move out of the bag, causing it to shrink rather than expand.