In class, I did an experiment with water and iodine solution in a beaker and also starch in a dialysis tube tied and placed in the beaker.

There were discussion questions I couldn't answer surely... please check my answers.

1. a)Use your results to determine the direction of net water movement in this experiment.
-water is moving into the starch solution

b)Is there a way to confirm this?
-increased water level of starch solution

2. Where was the concentration of water molecules greatest at the beginning of the experiment, inside or outside the tubing?
-outside of the tubing.

3. Explain the results of your experiment in terms of osmosis?
-because there was less water concentration in starch, the more concentration of water outside the tube went through the semipermeable membrane, or osmosis through to the starch solution.

Your answers are mostly correct! Let me confirm and provide some additional explanations:

1a) You are correct. In this experiment, the net movement of water was into the starch solution. This is because the starch solution had a lower concentration of water molecules compared to the surrounding water and iodine solution.

1b) To confirm the net movement of water, you can observe the change in water level in the starch solution. If the water level in the starch solution increased, it indicates that water moved from the surrounding solution into the starch solution.

2) The concentration of water molecules was greatest outside the tubing at the beginning of the experiment. This is because the starch solution inside the dialysis tube had solute particles (starch) that occupied space and reduced the concentration of water compared to the surrounding water and iodine solution.

3) Your explanation is accurate! The movement of water from an area of higher water concentration to an area of lower water concentration through a semipermeable membrane is known as osmosis. In this experiment, water molecules moved from the outside of the dialysis tubing, where the water concentration was higher, to the inside of the tubing, which had a lower concentration of water due to the presence of starch molecules. This resulted in the increase in water level in the starch solution.

Overall, your understanding of the experiment and the concept of osmosis seems to be correct!