Plan




My experiment is to investigate the effect of osmosis on potato tissue. In this experiment there are two variables (things that change to effect the results), which are; the mass change and the length change of the potato chip. From a preliminary experiment that I did, the results showed me that there was a large mass change in the chips and the length hardly changed at all. This shows that to be able to obtain some good results I will need to measure the change in mass.


Using the results from the preliminary experiment I have decided to use 5 different concentrations of Sucrose Solution to water because I will then be able to obtain a variety of results, which will give me a good overall percentage change for each of the solutions.


Sucrose Concentration (%)


Volume of 25% Sucrose Solution (cm)


Volume of Water (cm)


25


20


0


18.75


15


5


12.5


10


10


6.25


5


15


0


0


20


This is how I will do the experiment:


Collect all the equipment which will include;


15 Petri Dishes


1 potato


1 knife


Parapets


Measuring Cylinder


Filter paper


Sucrose Solution and Distilled Water


Cut the potato up into even sized small and thin slices


Weigh each potato chip and record


Measure out the concentration of the sucrose solution and the water using the measuring cylinder, and then place into the Petri dish


Place 3 potatoes in the Petri dish and close the lid, label and then leave to let osmosis take place


Repeat for the other 4 concentrations


After leaving for a certain time come back to the dishes and take the potato chips out


Blot each of the chips dry using the filter paper and then re-weigh each chip and record


Calculate the mass change and the percentage mass change


The equipment that will be in use in this experiment is Petri Dishes, a knife, and