required practical

• Step By Step:


  1. cut up a potato into identical cylinders
  2. get beakers with different sugar solutions (one should be pure water, anther should be very concentrated sugar solution and then others in between)
  3. measure the mass of the potatoes then leave one cylinder in each beaker for the same amount of time.
  4. after the time is up take the potatoes out and dry them and measure their masses again.
• What should happen?

  If the cylinders have drawn in water by osmosis they'll have increased in mass.

  if water has been drawn out they'll decrease in mass
• How to work out percentage change?

  change in value/original value x 100
• What is the dependent variable?


  The mass of the potatoes
• What is the independent variable?


  The concentration of the sugar solution
• What is the control variable?


  Volume of solution, temperature, time, type of sugar