Investigating Whether a Sugared Solution Has an Effect on Potatoes
Osmosis is the passage of water molecules from a weaker solution into
a stronger solution through a partially permeable membrane.
In this case, Osmosis applies to our practical because we are trying
to see if a sugared solution (sucrose) has an effect on potatoes. I
aim to investigate the effect of varying concentration of a certain
sugar solution on the amount of osmotic activity between the solution
and a potato chip of a given size. I will also endeavour to find the
exact (or as near as possible) concentration of sucrose solution when
no osmosis occurs and the concentrations are equal.
Preliminary Work
In a sense, preliminary work is as important as the actual experiment.
It allows you to make hypotheses before performing actual tests.
For my preliminary work, I used a 50 mm piece of potato. It was easy
to cut 50 mm (using a Vernier calliper) and to weigh them (using
electronic scales to two decimal places). We used 10 mls of sugar
solution/distilled water- this was the amount needed to cover one
piece of potato. This was put in a test tube along with a piece of the
potato and these were then put in a test tube rack. The first thing we
needed to observe was how different concentrations affected the weight
and length of the potato. We therefore needed to observe each end of
the spectrum. We tried 0.0 molar concentration (the lowest) and 0.8
molar (the highest.)
We then left each test until the next lesson, and then took the
measurement of the potato chips once more. This is my results table:
Concentration
Initial length
Final Length
Percentage difference
Initial mass
Final mass
Percentage difference
0 molar (water)
5 cm
5.15 cm
3 %
1.69 g
1.76 g
4.14 %
0 molar (water)
5 cm
5.2 cm
4 %
If we say that the right hand side in picture 1 is the potato, and the
Test tube A will have a piece of potato which is this size. Test tube
As my source of Catalase, I will use potato. This is easier to cut and
We then put the stopwatch on and left them for half an hour. After we weighed each potato tube and recorded our results. We did the experiment twice. We did this to make sure our results were correct. Preliminary method: We did everything the same as in our other experiment except we
was cut up into the smaller cubes, all 8000 of them. From there, I had
cork borer and a ruler. I will keep the potato chips the same size in
In the ruins of ancient Peru and Chili, the remains of potatoes dating back to 500 B.C. have been found. Potatoes were such a part of Incan life that they not only ate them, but they worshiped them. "O Creator! Thou who givest life to all things and hast made men that they may live, and multiply. Multiply also the fruits of the earth, the potatoes and other food that thou hast made, that men may not suffer from hunger and misery."- Incan Prayer used to worship potatoes.
Type of tissue- this will be controlled by using only one type of tissue, which is the potato
one gram of water by 1ºC. I chose to use water because it is safe,
the spores through the micro scope. It was to soon to see anything but little
Potato 2. Standard sugar solution (1molar) 3. Wash bottle 4. Test tubes and test - tube rack 5. Cork borer-size (4mm diameter) 6.
4. Put each group of potato discs in one of the 6 test tubes and watch
The experiment apparatus consisted of an extra-large egg, 1/10 spoon of salt, olive oil, water, a spoon, a small sized bowl, a Continental Electric egg beater, an 8” flat frying pan, a cooking stove, and a kitchen stopwatch.
"How Potato Chips are Made." State of Michigan. Michigan Department of Agriculture, 10 May 2007. Web. 12 Feb. 2010. .
Equipment Potato, Borer, Beakers, Measuring Cylinder, Stopclocks, Distilled Water, Electronic Balance, Salt solutions of various concentrations. Diagram [IMAGE] [IMAGE] [IMAGE] When we leave the potato in the solution for the allocated time, water