Making Indicators

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

Equipment:

• Red cabbage
•  tea
•  beetroot turmeric 
•  cranberry juice
•  a beaker 
• water 
• tripod
• Bunsen Burner 
• Gauze mat 
• 1.0 mol L-1 HCI
• 1.0mol L-1 NaOH.

Method:

For Beetroot and Cabbage:

• Cut the beetroot into small pieces until you have enough to fill 2 cups.
• Place the beetroot in a large beaker and add water to cover the beetroot.
• Boil over a bunsen burner for at least ten minutes for the colour to leach out of the beetroot.
• 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.
• Repeat this method for the beetroot. 

For the tea;

• Put 100 mL of water into beaker and boil.
• turn off the Bunsen Burner and put three tea bags in the beaker.
• Remove the tea bags when the tea is very strong.
• Place in a small beaker and leave to one side.

For the Cranberry Juice:

• Pour into a beaker and leave to one side.

For the turmeric

• Mix 1teaspoon turmeric in 100 mL cup of alcohol.
• Place in a small beaker and leave to one side

Photos: