Put 5 ml of fluid from beaker 7 and sac 7 into separate test tubes. Add a few drops of Lugol s solution. The appearance of dark blue precipitate indicates presence of starch. Record the result 8. Note the color of the water in beaker 8.
Phenolphthalein changes to red in an alkaline solution.
Sodium bicarbonate is also a very osmotically active solution. Note the change in weight. Explain the results in terms of osmosis. Be sure to explain your protocol carefully.