Procedure I ? Test Solution 1: Water
In this procedure you will explore osmosis when both solutions are identical (water).
Pick two different starting water volume settings between 1.50 L and 2.28 L for your trial 1 and trial 2 data runs. Record these values in Data Table I of your Activity Form.
- select Solution 1 by clicking or tapping on its button
- adjust the starting water volume to the desired trial value using the slider
- click the Start Data Run button ? monitor volume changes on both sides of the membrane
Note: allow 30 seconds for the data run to complete ? do not interrupt the data run - record final volume data in Data Table I
- take a screenshot of this completed data run (it will be used to confirm your identity and Activity Data Code)
- press the reset button and run your second trial (repeat steps 1-4) or move on to the next procedure
Procedure II ? Test Solution 2: Guanine solution (known concentration)
In this procedure you will explore osmosis when different solutions are separated by a semipermeable membrane.
Pick two different starting water volume settings for your trial 1 and trial 2 data runs. Record these values in Data Table II of your Activity Form.
- select Solution 2 by clicking or tapping on its button
- adjust the starting water volume to the desired trial value using the slider
- click the Start Data Run button ? monitor volume changes on both sides of the membrane
Note: allow 30 seconds for the data run to complete ? do not interrupt the data run - record final volume data in Data Table II
- press the reset button and run your second trial (repeat steps 1-4) or move on to the next procedure
Procedure III ? Test Solution 3: Cytochrome C solution (unknown concentration)
In this procedure you will again explore osmosis when different solutions are separated by a semipermeable membrane. Your data will allow you to determine the concentration of this test solution. Note: the concentration of this test solution is an unknown value and will likely be different for each user.
Pick two different starting water volume settings for your trial 1 and trial 2 data runs. Record these values in Data Table III of your Activity Form.
- select Solution 3 by clicking or tapping on its button
- adjust the starting water volume to the desired trial value using the slider
- click the Start Data Run button ? monitor volume changes on both sides of the membrane
Note: allow 30 seconds for the data run to complete ? do not interrupt the data run - record final volume data in Data Table III
- press the reset button and run your second trial (repeat steps 1-4) or move on to the post-activity work below
