Osmosis is the diffusion of water molecules through a semi permeable membrane.
Why is it important?
It is important to know what Osmosis is, and to understand it so that we understand what we are measuring, and so that we can use this understanding to apply to other situations so that we can gain further knowledge. We can also use this understanding to analyse our results.
What we will do:
We will put potato pieces of similar sizes in to test tubes of different concentrations of sucrose solution, and measure any changes in mass and length.
Affecting Factors:
There are a number of factors which can affect our results. We need to keep them all the same, and make sure that the only thing that changes is the concentration of the sucrose solution. These factors include: • Starting length of potato • Volume of Sucrose solution • Temperature of potato • Temperature of Sucrose solution • Time we left the potato in the Sucrose solution for
To control these factors, We will measure each piece of potato before the experiment, and make sure each piece is the same length. We will also measure out the volume of sucrose solution each time. We will also leave the potato pieces in the solution for the same amount of time.
We could also have measured the temperature of the sucrose solution and of the potato to make sure the temperature was always the same. However, we decided not to do this as we had a limited amount of time to conduct our experiment in, and we did not want to rush the rest otherwise we might have made a mistake, or been less accurate with either measuring the potato length and mass, volume of sucrose solution, or recording our results.
Prediction:
Based on what I know about osmosis, I think that the higher the concentration of sucrose solution, the more the potato mass and length will decrease. I think this based on my knowledge of osmosis. If I am correct, then when the water concentration in the