An experiment is designed to compare the effects of glucose and sucrose on the osmotic potential of a model cell. Two dialysis bags are used, one filled with a solution of 5% by mass glucose and the other with a 5% by mass sucrose solution. A given membrane is permeable to water but impermeable to glucose and
sucrose. Each membrane bag is then placed in a beaker of distilled water for two hours. The change in mass of the glucose bag is recorded below:
Solution (5% by mass) Initial Mass of Solution and Membrane Bag (g) Final Mass of Solution and Membrane Bag (g)
Glucose in Distilled Water 10.0
Sucrose in Distilled Water 10.0
13.2
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a. Describe the process of diffusion through the dialysis bags. (Note: Sucrose does not travel)
b. If you were to design a different experiment testing rates of diffusion, identify experimental procedures,
c. Analyze that data in the chart and describe the results. Predict the change in mass of the sucrose membrane bag, compared to that of the glucose membrane
bag. The molar mass of glucose is 180 g/mole, and the molar mass of sucrose is 342 g/mole. (Note: You do not need to calculate final mass.)
d. Based on the results, explain the increase in mass of the glucose membrane bag in terms of the movement of particles through the membrane. Provide
reasoning that describes how this relates to osmotic pressure.