AQA GCSE Biology Trilogy: Required Practical 3 (Osmosis)

Apparatus:

• Five potato chips
• Ruler
• Tile
• Five test tubes
• Pen to label test tube glass
• Five different concentrations of salt solution
• Balance  paper towels
• 10cm^3 measuring cylinder
• Test tube rack
• Stopwatch

Method:

1. Collect 5 potato chips.
2. Place them on a tile and, using a ruler, trim them all to the same length.
3. Pour 10cm^3 of different concentrations of salt solution into five test tubes and label the test tubes 1–5.
4. Measure the mass of one potato chip; record its mass and put it in one test tube.
5. Repeat this with the other four salt solutions so that you have one chip in each
   test tube.
6. Leave the potatoes in the test tube for as long as possible but at least 20
   minutes.
7. Remove the potato chips from the solution and place them on a paper towel to remove the excess liquid.
8. Measure the mass of the potato chips again and record the results.

Results: