Cabbage Lab
Part 1: Standardization
Procedure:
1. Add a squirt of each buffer into a test tube
2. Add just enough indicator (cabbage juice) to see a color change
3. Record the color change.
4. Save your test tubes to serve as color references for Part 2
Data:
Use a very basic color vocabulary so that someone else looking at your data would
understand it.
pH
Color Observed
0
2
3
4
5
6
7
8
9
10
11
12
14
Cabbage Lab: Crude Titration
Procedure:
1. Put 15 drops 1M NaOH into a test tube
2. Add 5-10 drops of cabbage indicator
3. Add 30 drops HCl drop by drop. After each drop, record the pH.
Data:
Drops Approx. pH
0
17
1
18
2
19
3
20
4
21
5
22
6
23
7
24
8
25
9
26
10
27
11
28
12
29
13
30
14
15
16
Conclusion:
1. Plot pH vs. # of drops. Fit your plot with a smooth curve and clearly mark
the neutral point on the curve.
2. Which is stronger based on molarity- the acid or the base? Explain.