Question

dialysis bags can be used as models of cells to explore the movement of materials into and out of cells. students set up an investigation with a dialysis bag containing a 2% iodine solution in a beaker containing a 9% starch solution as shown in the figure. starch turns blue - black in the presence of iodine. the dialysis bag is permeable to water and iodine but not to starch. which two observations most accurately predict what will occur in the investigation? (4 points) the mass of the dialysis bag will increase. the concentration of starch in the dialysis bag will increase. the solution in the beaker will turn blue - black. the mass of the dialysis bag will decrease. the solution in the dialysis bag will turn blue - black.

Explanation:

1. Water moves via osmosis from the beaker's lower solute concentration (9% starch) to the bag's higher solute concentration (2% iodine + dissolved solutes), increasing the bag's mass.
2. Iodine (small enough to cross the bag) enters the bag and reacts with the starch that diffuses into the bag from the beaker, producing the blue-black color. Starch cannot leave the bag, so the beaker solution does not change color, and starch concentration in the bag does not increase from internal production.

Answer:

1. The mass of the dialysis bag will increase.
2. The solution in the dialysis bag will turn blue-black.