Effect of Dilution of Solution on the Rate of Catalase Activity

The purpose of this lab was to change the rate of catalase activity, or how quick the reaction occurred. In the lab we were assigned to pick and choose a variable that would affect the reaction time of the floating disks. The variable chosen by my group was the dilution of the solution (H₂O₂). We added more and more water to see how the reaction time would change. We were interested to see how much of a difference the H₂O would make in the reaction time, while other groups changed simpler things such as temperature or the time soaking the disk in the solution. We agreed, before we collected our data, that if the dilution of the Hydrogen Peroxide was more diluted then the rate of catalase activity would slow down. From the beginning I personally expected to learn what affected the reaction time the best, and how you could speed up the reaction time. After the lab I've found out that by not adding H₂O to the H₂O₂ the reaction time will be the quickest of all.

The procedure our group went by was as followed:

1. Cut out paper disks

2. The person doing each step should remain constant throughout the experiment

3. Get liver solution (first solution being .05%)

4. Dip paper disks in solution

5. Drop disks in Peroxide and time until the disk rises to the surface

6. Do 5 trials per variable

7. Dilute liver solution with 5ml of H₂O

8. Repeat steps 2-5

9. Dilute liver solution with 10ml of H₂O

10. Repeat steps 2-5

11. Dilute liver solution with 15ml of H₂O

12. Repeat steps 2-5

13. Average out each tested variable

14. Don't forget to label

Dilution of Solution (ml) Trial 1

Trial 2 Trial 3 Trial 4 Trial 5 Average

.05% Liver

(no dilution) 4.3 sec 3.67 sec 4.01 sec 3.81 sec 3.39 sec 3.88 sec

.258 disks/sec

5 ml H₂O 5.11 sec 4.67 sec 5.3 sec 4.67 sec 4.65 sec 4.88 sec

.205 disks/sec

10 ml H₂O

6.31 sec 5.25 sec 6.19 sec 6.27 sec 4.96 sec 5.79 sec

.173 disks/sec

15 ml H₂O 7.35 sec 5.9 sec 5.63 sec 5.65 sec 5.47 sec 6.02 sec

.166