The reaction, x, will be directly proportional to y, the concentration of enzyme.
As the surface area of the potato is doubled the amount of oxygen released increases.
Plan
To make this experiment a fair test I am going to use a ruler to make sure each cylinder of potato cut using a cork borer measures 4cm long. I will also use 4cm long pieces for each test I do.
I am going to use 20cm of 20 volume Hydrogen Peroxide.
Throughout the experiment the amount of H O will need to remain the same.
Each time I will use a 4cm piece of potato. The first time I will just put the potato in the H O whole. The second time I will divide the potato into two pieces and so on continuing up to ten pieces going up in two's.
I am going to repeat each test three times, and then I will take the average for each set of results and plot them on the graph.
For each test I will record how many bubbles of oxygen are released in two minutes.
Below is a list of equipment I will need in order to do this experiment:
Beaker
Delivery tube
Test tube
Stop watch
Cork borer
Bench mat
Scalpel
Cutting tile
Report
I did not change what I did in my experiment from what I planned to do.
In my experiment I first cut out a 4cm cylinder of potato using a cork borer then I cut it into the desired amount of pieces.
I then added it to 20cm of H O , placed a rubber bung with a delivery tube on the test tube and times for two minutes how many oxygen bubbles were released out of the delivery tube and into the water.
Results
Graph
See graph paper for graph of average results.
Conclusion
My results are in a general pattern and contain no 'odd' results. As the greater the number of pieces of potato the greater the amount of surface area, which means the greater amount of oxygen bubbles released in the reaction.
My results do show that what I said in my prediction is correct.
The greater the surface area the greater the reaction.
Evaluation
In order to improve on my experiment I could have used a wider range of pieces of potato, to see what happens when a far greater amount of potato pieces are used.
I did not obtain any anomalous results, this is because as you increase the surface area you increase the rate of reaction causing the results to go up each time. You would not get results that went up then went down unless there was a problem with a vital piece of equipment, i.e. H O , the potato, or the means of measuring.
