the potato catalase pre-lab
DESCRIPTION
The Potato Catalase Pre-Lab. Potato Catalase Experiment. 100 g of potato were cut into small chunks. Potato Catalase Experiment. The chunks were put into a blender along with 200mL of water. Potato Catalase Experiment. The mixture was then pureed at high speed for 1 minute. - PowerPoint PPT PresentationTRANSCRIPT
The Potato Catalase Pre-Lab
100 g of potato were cut into small chunks
Potato Catalase Experiment
The chunks were put into a blender along with 200mL of water
Potato Catalase Experiment
The mixture was then pureed at high speed for 1 minute
Potato Catalase Experiment
The puree was then poured through a wire sieve
Potato Catalase Experiment
The sieve separates out the foam and the larger chunks of potato
Potato Catalase Experiment
The foam is then discarded
Potato Catalase Experiment
Household vinegar and ammonia were used to adjust the pH of the potato extract
Potato Catalase Experiment
A 25mL graduated cylinder was used to measure out 6mL of potato extract which
was then added to each test tube
Potato Catalase Experiment
To ensure valid results, the graduated cylinder was rinsed out between measurements
Drops of vinegar or ammonia were then added to each test tube to obtain the
desired pH as shown in the table below
Potato Catalase Experiment
pH 6 pH 7 pH 8 pH 9Vinegar 2 drops 0 drops 0 drops 0 drops
Ammonia 0 drops 0 drops 2 drops 4 drops
Distilled Water 2 drops 4 drops 2 drops 0 drops
3mL of hydrogen peroxide (3%) were then poured into each of four smaller test tubes
Potato Catalase Experiment
The 3mL samples of hydrogen peroxide were then added to each test tube and stirred for 2 seconds
Potato Catalase Experiment
To improve validity, H2O2 was added working left to right, and then each mixture stirred working left to right.
After 2 minutes, a marking pen was used to indicate the upper and lower limits of the foam columns.
Potato Catalase Experiment
To make measurements valid, the marking was also done working left to right.
The data table below shows the results of 3 trials.
Potato Catalase Experiment
Potato Catalases & Hydrogen Peroxide Foam Heights (mm)
Trial 1 Trial 2 Trial 3 Average
pH 6 14 15 13 14.0
pH 7 28 27 28 27.7
pH 8 46 44 44 44.7
pH 9 25 23 25 24.3
Three trials helps make the results more reliable. More trials would be even better.
Foam Height (mm) as a function of the effect of pH on Catalase Activity
Potato Catalase Experiment
pH6 7 8 9
Aver
age
Foam
He
ight
(mm
)
454035302520151050
44.7mm
24.3mm
14.0mm
27.7mm