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             To compare the action of catalse to a non-protein catalyst under different conditions.
            
             Please refer to the procedure in the Enzyme lab handout. .
             Method/Procedure:.
             Please refer to the procedure in the Enzyme lab handout.
             Hypothesis:.
             The non-protein catalyst (potato) will be less active when compared to the catalase in the liver. This is due to the fact that the liver has a more concentrated active catalyst than the potato. Furthermore, crushing either item will increase the rate of reaction because when crushed the liver and potato have a higher surface area and will react faster.
             Analysis.
             1. In part A the gas which evolves is oxygen. The chemical reaction of this is as.
             follows:.
             .
             2. Yes, H2O2 can be broken down by catalysts other than those found in living systems. An example of such a catalyst is MnO2. This is possible because .
             3. An increase of temperature slows down the rate of reaction. This is due to the fact that proteins, protein enzymes, and other organic catalysts can slightly denature in a hot environment. .
             Particle size increases the rate of reaction by providing a larger surface area for the catalyst to have more sites of interaction with the H2O2. .
             Reusability has little effects on the rate of reaction. When the used piece of liver was added to the fresh H2O2 the reaction preceded exactly the same as the original reaction with the fresh liver. This is because the catalyst is not used up in the reaction and can be extracted in its original form.
             4. Our results would have been the same because we are testing the catalyst in the liver. I assume that a dog liver contains the same catalase as the cow liver that we used; therefore, the results would be the same.
             5. We used liver because it contains the protein enzyme, catalase in large amounts.
             Conclusions.
             With both the catalase, and non-protein catalyst:.
             - An increase in heat decreased the rate of reaction. .
             - A decrease in heat decreased the rate of reaction.