Osmosis in Potatoes

Aim: To investigate osmosis using potatoes.

Method: 

1. Mark the value of one solute concentration on one tube and repeat using a different tube for each concentration. Fill each tube two-thirds full of the approprite solution.

2. Blot a piece of potato dry on a paper towel, then measure and record it's mass. Use the forceps to place it into one of the tubes, and record the tub. Repeat for all tubes.

3. After 20 minutes, use the forceps to remove each piece of potato, blot it dry and measure it's mass again. Record all final masses.

Results: The percentage chnage in mass of each potato slice and is calculated and recorded, indicating whether mass was gained or lost.

Conclusion: The results show that when the solution concentration is very dilute, water enters the potato cells. This is due to osmosis becuase the solute concentration of the potato cell is greater than the surrounding solution. As the solute concentation of the solution increases above that inside the potato cells, osmosis causes water to be lost from the potato.