Making Indicators

Making Indicators: Cabbage  

Aim: 

To make acid-base indicators using everyday substance. 

Equipment:

Red cabbage, a beaker, water, tripod, Bunsen burner, gauze mat, 1.0 mol L-1 HCI and 1.0 mal L-1 NaOH.

Method: 

Chop the cabbage into small pieces until you have enough to fill 2 cups.

Place the cabbage in a large beaker and add water to cover the cabbage. 

Boil over a Bunsen burner for at least ten minutes for the colour to leach out of the cabbage.

Filter out the plant material to obtain a red-purple-bluish coloured liquid. This liquid is at about pH 7. (The exact colour you get depends on the pH of the water.) 

Place in a small beaker and leave to one side.



Here are my results 

When I added HCI (Acid) to cabbage it turned red. When I added NaOH (Alkali) it turned green.

The other indicators here were made by my other classmates.

When HCI (Acid) was added to Tea it turned yellow. When NaOH (Alkali) was added to tea it turned Yellow

When HCI (Acid) was added to Tumeric it turned yellow. When NaOH (Alkali) was added to Turmeric it turned red.

When HCI (Acid) was added to Cranberry it turned a pink-red colour. When NaOH (alkali was added to Cranberry It turned green.

When HCI (Acid) was added to beetroot it turned red. When NaOH (alkali was added to beetroot it turned yellow.

Cabbage boiling 

All indicators with HCI(acid) and NaOH (alkali)

Conclusion:

We successfully made acid-base indicators using everyday substances. It wasn't hard at all. I think the Cabbage worked the best when adding acid and base because of the colours changes that happen.