The Effect of Changing the Concentration of Sucrose on the Movement of Water into a Potato

The Effect of Changing the Concentration of Sucrose on the Movement of Water into a Potato

Introduction

Aim

1. To use different concentrations of sucrose solution to determine

the internal concentration of the potato.

2. To use different concentrations of a solution more dilute than the

internal concentration of the potato to find out what the effects of

different sugar concentrations have on the movement of water into the

potato.

Theory

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Osmosis is the movement of water from a dilute solution to a more

concentrated solution, through a partially permeable membrane, until

the concentrations are equal. Linking this to my aim, we need to find

out the internal concentration of the potato so that we will know

which concentration of sucrose solution will make water move into the

potato, though Osmosis. Once we have done this, it is possible to

increase the dilution to find out the effects that different sucrose

concentration have on the movement of water into the potato.

Prediction

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1. If the internal concentration of the potato is the same as the

concentration of the solution, then osmosis will not happen and the

weight will remain unchanged.

2. The more dilute the solution, the greater the movement of water due

to osmosis and therefore the greater the change in weight.

Fair testing

============

Firstly, we are using six discs in each measuring beaker. This is to

make sure that when cutting up the potato cylinder into 0.5cm discs we

know that the surface area of 1 potato disc will measure out the

surface area of another.

Then, we are going to leave them for 24 hours. This is to make sure

that all the Osmosis that is going to happen will happen. Also they

will be kept in the same place so that the temperature will always be

the same at every point of the 24 hours.

Thirdly, we are going to cover them with cling film so that the water