Parts 1 and 2

Each group needs:

• 10 clear 6-8-oz. cups or Dixie cups to hold test materials
• Masking tape and pen (for labeling cups)
• The following 10 test materials:

1. Vinegar (2 samples of about 2 tablespoons each)
2. Lemon juice (about 2 tablespoons)
3. Tomato or apple juice (pure) (about 2 tablespoons)
4. Distilled water (2 samples of about 2 tablespoons)
5. Salt water (2 tablespoons of this mix: 3 tablespoons salt in 1 cup distilled water)
6. Household liquid bleach (about 2 tablespoons)
7. Milk of Magnesia (about 2 tablespoons)
8. Baking soda (about 2 tablespoons in 1 cup distilled water)
9. Alka-Seltzer tablet
10. Alka-Seltzer tablet

• Plus the specific items below, for Part 1 or 2.

Part 1 (only)

Each group needs:

• 30 1.5-inch strips of wide-range (0-14 pH) litmus paper and comparison chart. Students need to use the comparison chart included with the litmus container, so obtain enough dispensers for each group to have one. Purchase litmus paper from a chemistry supply company (such as Fisher) or a well-equipped hardware store.
• pH Values of Common Substances attachment (or as an overhead projector transparency for the entire class to view)
• Measuring pH of Common Substances Data Sheet, and Measuring pH of Common Substances Worksheet, one per student

Part 2 (only)

• Copies of the Cabbage Juice Rainbow Data Sheet, one per student
• Copies of the Red Cabbage Indicator Color Chart (one per group, or one color overhead projector transparency for the entire class to view)
• Cabbage juice for the entire class to share (see materials list, below)

Part 2: Preparation of red cabbage juice for the entire class to share (10 groups):

• 1 small red cabbage
• Cold, distilled water
• Blender (for teacher use only)
• Fine mesh strainer (or funnel and a few coffee filters)
• Large pitcher or beaker
• 10 small jars, beakers or containers (500 ml size, 1 per group)

Alternate Setup: To reduce cost and preparation time, make one sample of each solution and have the students rotate through the samples (instead of each group having each sample). Make numerous water and vinegar samples so that each group has a sample in which to put the Alka-Seltzer. Have each group be in charge of using cabbage juice to test just one of the samples and share data as a class.