# Investigate the Effect of Varying Solution Concentration on Osmosis in a Potato Chip

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Investigate the Effect of Varying Solution Concentration on Osmosis in a Potato Chip

Prediction

A definition of osmosis is: 'the movement of water molecules from an area of high water concentration to a low water concentration across a semi-permeable membrane' (Oxforddictionary 2000).

In a high concentration of water the amount of solute (e.g. sugar) is low. These solutions are usually known as a dilute or weak solution.
But in a low concentration of water the amount of solute (e.g. sugar) is high. These solutions are usually known as concentrated or strong solutions. When a weak solution and a strong solution are separated by a partially permeable membrane, the water will move from the area of high concentration to the area of low
Using this information, I have come to the prediction that with a high concentration of sucrose in the water, the mass of the potato will decrease and the cells will become plasmolysed. In a low concentration of sucrose the cells will become turgid.

Preliminary work

I have based my prediction on a prelimary experiment we did amongst our class, this experiment involved us placing potato chips into various concentrations of sucrose solution and observing the potato's change in mass according to the solution they were placed in.

Carrying out a preliminary experiment helped me to decide how long to leave the potato chips in the sucrose solution. In the preliminary I left them for 24hrs however I found this an insufficient time and this helped me to decide on leaving the potato chips for 2hrs in the final experiment. Preliminary Experiment Results
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solution mass before mass after 24hrs change in mass

0 1.5 2 0.5 0.1 1.7 2 0.3 0.2 1.6 1.8 0.2 0.3 1.6 1.9 0.3 0.4 1.5 1.9 0.4
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Variables

In order to create a fair test, certain aspects of the experiment will have to be kept the same whilst one key variable is changed. In my experiment, I have chosen to