Osmosis with Potato Chips

My Investigation on osmosis

Osmosis is a special kind of diffusion. While diffusion can describe the movement of any kind of molecule, osmosis is only about the movement of water molecules.

To show this diffusion I will be using potato discs, of the same size and mass, in different concentrations of sugar solution to find out whether the mass of the discs increases or decreases depending on the concentration.

I predict that when the sugar solution is 0% the mass will increase as there is less sugar in the water than in the potato. The water will then travel through a partly permeable membrane into the potato from outside. When the sugar solution is 20% the mass of the potato will decrease as there is more sugar in the water then in the potato.

Apparatus:

• 5 Boiling tubes

• Cork borer

• Electric balance

• Water

• Sugar

• Scalpel

Safety:

• Make sure you are careful with the scalpel and wear goggles

• Make sure all pieces of potato are removed from the floor

Method:

• Make sure you have all your apparatus set up and are aware of all safety aspects

• Using your cork borer, cut a few cylinders out of the potato

• Then get the scalpel and cut the cylinders into smaller discs

• Weigh the discs of potato and make sure they are all the same mass

• Then put three cylinders in each of the boiling tubes

• Add the five solutions, one to each boiling tube

• Leave the discs over night in their solutions

• Next day, weigh the discs again and record the results in a results table

Fair test:

I can make this investigation a fair test by only changing the concentration of the solutions. The rest will remain the same; the size of the potato discs, volume of the solution, and temp as this will then be fair.

Analysis:

I have discovered that as I predicted some of the potato chips lost weight and some gained weight. The predictions I made have been proved correct. My results show that if thee is less sugar in the solution then in