From the bar graph (fig.3), which portrays the raw results, it is observed that there is a consistent decrease in the volume of the oxygen produced (cm3), as the concentration of the CuSO4 increases. However, not only the quantitive data which was observed and calculated, but also some physical changes were noticeable during the experiment.
When the hydrogen peroxide was added to the live alongside the buffer solution with the CuSO4 , lots of fizzing and bubbles would appear. Moreover, although the temperature increase was not measured, the test tube would feel a lot warmer, once the chemicals were added on to the liver extract. Furthermore, the experiment was held over the course of several days, so the liver extract had to be refrigerated and was left left air and light exposed for a relatively long time, therefore the enzyme activity and efficacy might’ve been affected, resulting in the alteration of the results or some anomalies, for example in trail four for the concentration 0.8 mol of CuSO4, in trail three for the concentration 0.6 of CuSO4.Overall, the results of the experiment do provide evidence and prove the original hypothesis of the paper, which states: “By increasing the concentration of the copper sulphate (CuSO4), the activity of the enzyme catalyse will decrease.” and that behaviour is known to be or similar to that of an inhibitor.
There was less oxygen produced consistently as the concentration of the CuSO4 was increased by 0.2 mol dm-3 as it is seem from the progressive decrease from the average values of the O2 produced for each concentration : ( 33.5, 26.0, 20.5, 14.
25 and 9.5) resulting in a downward slop line of best fit. (fig.4) Therefore if higher concentration of were CuSO4 used, the CuSO4 would alter the shape of the active site, so that it is not able to interact with the hydrogen peroxide nor catalyse it.
Thus there will be no oxygen production. This is because CuSO4 is an irreversible inhibitor due to the heavy Cu2+ metal ion. The ion reacts with the sulohydryl groups and thus results in changing the chemical structure of the active site. this means that the inhibition of the hydrogen peroxide is competitive. Furthermore, during the experiment that the temperature of the test tube got warmer during the reactions of the lower concentrations of the CuSO4 , but not necessarily in the higher concentrations. This is because with higher concentration, the volume of the oxygen produced was much less than with lower concentrations. This means that the reaction is exothermic and released energy making the test tube become warmer. While with the higher concentrations of CuSO4 , this did not occur since less hydrogen peroxide was decomposed, hence less oxygen was produced, and the reaction rate was much slower thus the heat emitted was not noted.
Even though the results showed an inverse relationship between the CuSO4 and the hydrogen peroxide, there some anomalies in the results as mentioned before: for example in trail four for the concentration 0.8 mol of CuSO4, in trail three for the concentration 0.6 of CuSO4. The presence of an anomaly means that there was a percentage error and percentage uncertainty which might have affected the results.
However, the anomalies present didn’t affect the overall conclusion of the experiment and it is still reliable. This is because a lot of trails were carried out for each of the concentrations, then the average of results was calculated and the results did show a clear pattern of decrease of the volume of oxygen produced.