2 If you can cut the chips an hour before the lesson and leave them in a large bowl of water, they will be fully turgid at the beginning of the experiment.In this case, all the chips will lose mass in the blackcurrant squash solutions (0% blackcurrant squash solution will stay the same). Otherwise, the chips in 0% blackcurrant squash solution will gain mass and the rest will probably lose mass.
A high-level GCSE group could assess the range of measures using maximum and minimum bars.
From the graph you can read off the ‘blackcurrant squash equivalent’ concentration of the potato cell contents – this will be the concentration at which the mass of the potato stayed the same, or may be interpolated between two concentrations.
In this investigation, you prepare a range of dilutions of blackcurrant squash.
Cut potato chips, weigh them and place them in the various solutions. Remove the potato chips from the blackcurrant squash, dry and reweigh.
This potato is then placed in a beaker containing coloured water for some time.
When a plant cell is placed in hypertonic solution, the process of exosmosis starts and water from the cell sap diffuses out into the solution of external medium.
Undiluted blackcurrant squash contains 23% juice or 556 g dm.
You can modify this activity to show the rate of movement of water by osmosis.
Every 10 minutes, remove one set of chips, dry on paper towel and reweigh.
Find out how long it takes before there is no further change in mass.