At what pH does the enzyme called peroxidase work best The purpose of my investigation is to find out at what pH the enzyme called peroxidase works best. We can find the peroxidase enzyme if we grind celery or most other animals and plants. A chemical reaction in plants and animals produces hydrogen peroxide, which can poison them if it is allowed to build up. The peroxidase enzyme acts as a catalyst for the decomposition of hydrogen peroxide, which is broken down into water and oxygen. The reaction is: 2H20 = 2H20 + O2(Aq) (L) (G) I'm going to measure the amount of oxygen emitted by the celery at different pHs and whatever pH helps the enzyme produce the most oxygen. Before I do that I need to make a preliminary plan to see what my other variables should be so I can get the best results. I predict that the optimal pH will be around 7 because if it were to go lower or higher than this it could change the enzymes shape and/or charging properties of the substrate so that the substrate cannot bind to the active site or cannot undergo catalysis. Different enzymes have different optimal pHs and it is difficult to say which one it will be because some enzymes work better at low temperatures and others at high temperatures. As you can see from the graph the two different enzymes, represented by the red and green lines, have a different optimal pH. When the pH is altered it will become denatured or it may be optimal, it depends on what is the best pH the enzyme responds to. I believe it will be 7 because it is in the middle, 7 is not too high or too low but could be wrong depending on the enzyme. I think it's pH7 because that's... middle of the paper... way more. I would also try to make the celery the same age because of my experiments in two days with two different celeries, that could have had an effect and given strange results. However, the strange results could come from anything, we may have measured slightly incorrectly, measured the solutions incorrectly, or when we measured the solutions, there may have been some acid left in the syringes. I finally managed to get results that made sense after repeating tests that had strange results. But overall I successfully conducted my investigation fairly and thoroughly. My experiment went well because I accurately measured all of my solutions, added the solutions in the same order, timed the experiment to the best of my ability, kept the temperature the same, and produced a fair and accurate experiment.