Practical

• Step 1: Cut up a potato into identical cylinders, and get some beakers with different sugar solutions in them. One should be pure water and another should be a very concentrated sugar solution. Then you can have a few others with concentrations in between
• Step 2: You measure the mass of the cylinders, then leave one cylinder in each beaker for 24 hours
• Step 3: Then you take them out, dry them with a paper towel and measure their masses again
• Step 4: If the cylinders have drawn in water by osmosis, they'll have increased in mass. If the water has been drawn out, they'll have decreased in mass. You can calculate the percentage change in mass, then plot a few graphs and things.
• Variables:

  • Dependant variable is the chip mass
  • Independent variable is the concentration of the sugar solution.
  • Control variable is the volume of solution, temperature, time, type of sugar used, ect...)
• A possible error is if some potato cylinders were not fully dried, the excess water would give a higher mass, or if water evaporated from the beakers, the concentrations of the sugar solutions would change. You can reduce the effect of these errors by repeating the experiment and calculating a mean percentage change at each concentration