Practice Lab Practical on Diffusion and Osmosis

1. The above diagram depicts a dialysis tube with both ends tied immersed in a beaker of solution. The dialysis tube contains 1000 particles of glucose, 100 particles of starch, and 100 particles of chloride in water. The dialysis tube is permeable to chloride and impermeable to glucose and starch. The solution in the beaker is pure water.
   1. 15 minutes after immersion, will the weight of the tube increase or decrease?
      Look here for the answer Increase
   2. 15 minutes after immersion, Raj tested the water in the beaker for chloride and for starch. What were his results?
      Look here for the answer Positve for chloride and negative for starch
   3. 15 minutes after immersion, Raj also tested the water in the tube for chloride and for starch. What were his results?
      Look here for the answer Positive for both

   

2. 5 dialysis bags (A-E) containing varying concentrations of sucrose solution were placed in beakers of pure water. The above graph show the change in the weight of the bags versus time.
   1. Which bag initially had the highest [sucrose]?
      Look here for the answer B
   2. Which bag initially had the lowest [sucrose]?
      Look here for the answer D

3. Answer the following questions with True or False.
   1. Diffusion is the movement of molecules from an area of low concentration to an area of high concentration
      Look here for the answer False
   2. Diffusion is a process that requires no energy
      Look here for the answer False
   3. Diffusion is NOT necessary for human life to proceed
      Look here for the answer False
   4. Osmosis is a type of diffusion
      Look here for the answer True
   5. Osmosis is an example of passive transport
      Look here for the answer True
   6. If you place a cell in an isotonic solution, the size of the cell will increase.
      Look here for the answer False
   7. If you place a cell in a hypertonic solution, the size of the cell will decrease.
      Look here for the answer True

   

4. Consider the following solutions separated by a membrane (pink line) that is permeable to water (blue) but impermeable to glucose (green circles).
   1. Which solution has a greater osmotic pressure?
      Look here for the answer B
   2. In which solution will water volume decrease after osmosis has occurred and equilibrium been reached?
      Look here for the answer A
   3. Which solution was hypertonic to the other?
      Look here for the answer B
   4. Which solution was hypotonic to the other?
      Look here for the answer A

5. Answer the following questions with Increase, Decrease, or Stay the same.
   1. As the kinetic energy of a group of molecules increases, their rate of diffusion will:
      Look here for the answer Increase
   2. As temperature decreases, kinetic energy will:
      Look here for the answer Decrease
   3. As a molecule’s mass increases, its rate of diffusion will:
      Look here for the answer Decrease

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