Introduction & Hypothesis
In this experiment we will investigate the effect of solute concentration on osmosis by placing dialysis bags in the appropriate solution and recording the change in the weight of the bag over a period of 40 minutes. Furthermore, our hypothesis for Bag 1 is that water will move from the beaker to the dialysis bag because bag has higher concentration of solute. Hypothesis, Bag 2: Water will move from bag to the beaker because beaker contains higher concentration of solute. Hypothesis, Bag 3: Water will move in and out because bag and beaker contain same concentration.

Materials & Methods:
1. Labeled three 400ml beakers 1-3. Added 200 ml of distilled water to beakers 1 and added 200 ml of 10% sucrose solution to beakers 2 and 3.
2. Obtain three sections of dialysis tubing that have been soaking in water. Twist and tightly tie one end of each dialysis tube with four inches cotton string.
3. Pipetted 10 ml of the following solutions in to each bag and tie the end of the bags: Bag 1: 10 ml of 10% sucrose Bag 2: 10ml of distilled water Bag 3: 10 ml of 10% sucrose
4. Rinse each bag with tap water and blot off water with paper towels before weigh each bag with digital balance. Place the initial mass in the “0 Minute” column of the below table.
5. Place the bags in their corresponding beakers at room temperature and record the change in the weight of the bag over a period of 40 minutes. Results:
Changes in the mass of dialysis bags

Bag Contents (10 ml)
Beaker Contents (200 ml)
0 min
40 min
Total Mass Change
1
10% Sucrose dH2O 10.336 g
11.976 g
1.64 g
2
dH2O
10% Sucrose
7.009 g
6.525 g
-0.484 g
3
10% Sucrose
10% Sucrose
6.25 g
6.25 g
0 g
Figure 1. Quantifying changes in the mass of dialysis bags due to osmosis.

The masses of dialysis bag 1 and 2 changed (bag 1 gain mass and bag 2 lose mass) because water moved from a higher