Carrot serves as semi-permeable membrane to illustrate osmosis
Materials Required:
- carrot (large)
- #3 rubber stopper
- glass tubing, 4' or 8', to fit stopper
- 2L TF glass cylinder
- water
- Karo® syrup
- ring stand and clamps
- pointer/indicator to follow progress of syrup rising in glass tube
Procedure:
- drill hole into carrot, a 13/16" Forster® bit and drill press works much better than other methods
- arrange cylinder, glass tube and stopper as shown in simplified illustration
- fill cylinder with distilled water to within 2-inches of top
- fill carrot with Karo® syrup
- carefully fix stopper and glass tube into carrot,
- lower carrot into water in cylinder
- mark the initial miniscus (see photo), and observe rise of liquid in glass tube
*Try adding acrylic paint tint to Karo® Syrup for better viewing of tubing
Simplified illustration; the mold that forms if the apparatus is not cleaned promptly
Photos:
