Making an Indicator

Aim: To make acid-base indicators using everyday substances.

Equipment:

• Red cabbage
• a Beaker
• Water
• Tripod

Method:

1. Chop the cabbage into small pieces until you have enough to fill 2 cups.
2. Place the cabbage in a large beaker and add water to cover the cabbage.
3. Boil over a bunsen burner for at least ten minutes for the colour to leach out of the cabbage.
4. Filter out the plant material to obtain a red-purple-bluish colour liquid. This liquid is at about pH7. ( The exact colour you get depends on the pH of the water.)
5. Place in a small beaker and leave to one side.

Results:

Discussion:

After we boiled the cabbage, Using a pipet we dropped a few cabbage indicator unto the spotting tile, we did the same thing with the other indicators like tea, cranberry, turmeric and beetroot. We then dropped a few HCI (acid) into some of the indicators. While on the rest we used NaOH(Alkali-base)

Conclusion:

We successfully made our indicators and came up with a result for each one.