MISEP Chemistry 512 – Jacobs
Enzyme Catalyst Lab - Formal Report – August 8, 2007
ABSTRACT
This investigation examined what would happen to the rate of an enzyme-catalyzed reaction if the concentration of substrate changed. We hypothesized that if the concentration increased, then the reaction rate would also increase. To test our question, we varied a combination of substrate and buffer, totaling 6mL, with a constant amount of 2 drops of catalyst. The enzyme catalyst, peroxidase, increased the rate of the reaction. The results of our experiment can be found by comparing the reaction rates for each trial. These rates are actually the slopes of the lines that were graphed during each reaction. The trend of data …show more content…
Place the chicken liver enzyme into a cold bath to maintain a cold temperature.
In separate graduated cylinders, measure out 2ml of substrate and 4ml of buffer and pour both into a test tube. Add 2 drops of catalyst. Cap immediately with LabPro stopper, and start the computer measurement program. Stop recording once the stopper pops off.
Using the software, find the slope of the line, which will represent the reaction rate. Print the graph for your records.
Repeat steps 3 and 4, increasing the substrate by 1 mL and decreasing the buffer by 1 mL, keeping the total volume at 6ml. Do this until you reach 6mL of substrate and 0mL of buffer. (See data table)
Compare reaction rates using the different slopes from the varying concentrations.
RESULTS
DATA TABLE
Substrate
(H2O2)
Buffer
(H2O)
Enzyme Catalyst
(Peroxidase)
Reaction Rate (Slope)
6ml
0ml
2 drops
0.663 kPa/s
5ml
1ml
2 …show more content…
Our results showed that the reaction rate and concentration of substrate are proportional. Why this happens is interesting. A reaction is the change of the substrate into a new and different thing, called the product. The collision theory states that reactions happen as molecules collide, but they must collide at the correct orientation so that the activation sites on the molecules will match up. If you can increase the number of molecules in a reaction, you will also increase the chances of having the molecules collide. When we increased the concentration of substrate we increased the number of molecules, and thereby increasing the chances of the molecules colliding. So increasing the concentration of the substrate increased the rate of the