After finishing the practical section of this experiment, I recorded all the results in a table and constructed two graphs. One of the graphs represents the rate of the reaction on the vertical (y axis), and the pH on the horizontal (x axis). The other graph I drew, shows the time in seconds on the y axis, and the pH on the x axis. Table of results: Solution Tube Time 10 denatured When I had collected in all of the times, I converted them into seconds in order to finally find out the rate of the reaction.
The process by which this is accessible is done using the following technique- rate = 1/time in seconds (x constant (10,000)). When I had finished the conversion I constructed another table. Table of results: Solution Tube Time in secs Rate of reaction denatured dentaured Once I had calculated all of the rates for each solution tube, I was able to construct the two line graphs.
Looking at the graph representing time against pH, you can see quite clearly that there is a pattern. Once the results have been plotted there is a clear shape that has formed, which is most likely not a coincidence, as it must have something to do with the pH. You will notice that the solutions with pH between 1. 3 and 1. 7 seem to have the lowest reaction time, whereby all of the egg suspension has vanished and the solution returned to its initial clear colour. It is apparent that the solutions with a pH lower than 1. 3 and higher than 1.
7 are not the optimum pH, as the reaction times are much slower. Another clear observation is that a solution with pH more than 2. 3 subsequently denatures, this is a slight flaw in the set-up which cleverly attempts to catch you out. When you observe the graph showing the rate against pH, another clear trend is apparent, where the shape of the line is very similar to that of the one in the first graph. The curve this time though is the other way around, this must have something to do with the conversion of time into the rate.
It shows that the pH between 1. 3 and 1. 7 is has the highest rate of reaction, meaning that it is a quicker reaction. The solutions with a pH either side of 1. 3 and 1. 7 have lower rates, meaning a slower reaction. Although looking at the graph more closely, it is apparent that the optimum pH for a reaction is 1. 3, as it has the highest rate of reaction in all of those tested. From the line of best fit on both graphs, it is clear that some of the points do not exactly fit. They are anomalies.
Although they have only slight inaccuracies, they are an indication of possible errors in the investigation, there could be many reasons for this, for example, maybe I measured out the acid to a slight differential volume than was expected, but these things are only minute. As long as you can see the general pattern that arises, then a general conclusion can be formed. The measurement of the time taken for all of the egg suspension to disappear is probably the most likely to cause an interference in my final results.
Another example could be that there was a slight temperature fluctuation which could have caused the reaction rate to increase slightly. There are some suggestions and improvements which can be made, and these are for example, to procede with only one solution at a time, this would make the overall experiment much slower, but you would be able to obtain better and more reliable results, especially when you have the chance to concentrate on one tube in the water bath, making the time taken for the reaction to take place much more reliable. This will ultimately reduce the amount of errors in the investigation to a substantial degree.