AP Lab Skills Guide
AP Lab Skills Guide
AP Lab Skills Guide
+
Tube 1 (substrate)
H2O2
Guaiacol
Distilled H2O
Mix contents
Begin Timing
Tube 2 (enzyme)
Peroxidase
Distilled water
Tube 3
(tubes 1 + 2)
Begin Timing
AP Lab Skills Guide
Each minute for 5
min compare the
color of tube 3 to the
standard
Tube 3
(tubes 1 + 2)
Begin Timing
Time (min)
Color
1
1
2
2
3
4…
Graph the data…
AP Lab Skills Guide
Time (min)
Color
1
1
2
2
3
2
4
3
5
5
6
6
7
8
8
10
Each minute for 5
min compare the
color of tube 3 to the
standard
You are determining how long to let the reaction go to get a
value of “5” as your baseline for comparisons in the next
step…you will see…we will run all future reactions for 5
minutes and look at color and compare to enzyme in distilled
water….
AP Lab Skills Guide
AP Lab Skills Guide
Tube 1
Peroxidase
H2O2
pH 2 buffer
Tube 2
Peroxidase
H2O2
pH 4 buffer
Tube 3
Tube 4
Peroxidase
H2O2
pH 6 buffer
Peroxidase
H2O2
pH 8 buffer
Tube 5
Peroxidase
H2O2
pH 10 buffer
Tube 6
Peroxidase
H2O2
pH 12 buffer
Cover with parafilm, gently mix and measure color at 0 minutes
and color change at time determined in part 1 (5 minutes)...
AP Lab Skills Guide
pH
Color
2
1
4
2
6
5
8
3
10
1
12
1
Of course, we should combine the class data, take averages, SD,
SE and graph with error bars…
AP Lab Skills Guide
AP Lab Skills Guide
AP Lab Skills Guide
AP Lab Skills Guide
AP Lab Skills Guide