Investigating osmosis
Label six test tubes / boiling tubes with the concentration of Sucrose solution to be used.
Fill the tubes with 10 ml of the prepared sucrose solution at the correct concentration. 3.Cut 6 potato pieces to the size secified and dry them on a paper towel 4.Weigh the potato pieces using a balance and record masses in an appropriately designed table.
Place potato pieces in a beaker/ boiling tube. The solutions should completely cover the chips.
Leave for 30 minutes.
Remove potato pieces one at a time from the beakers/ boiling tubes. 8. Dry the potato pieces on paper towel.
Calculate the change in mass and the percentage change in mass of each set of potato pieces.
Plot percentage change in mass (y-axis) against concentration of Sucrose solution (x axis).
Calculate the percentage change in mass using the formula below:
% change in mass = final mass – initial mass x 100%
Initial mass
Where there is no net gain or loss in mass, ψCELL is equal to ψBATHING SOLUTION. From your graph read the molarity of sucrose where the percentage mass change is zero. 15. From the table below, find the water potential of a sucrose solution of that molarity