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Tuesday 4 June 2019

Science Testing pH

Aim: To test the pH of a range of household chemicals.

Equipment: A variety of household chemicals, spotting tile, red litmus paper, blue litmus paper,
Universal indicator solution, safety glasses.

1) Add a few drops of each chemical to a spot on your spotting tile. If a substance is solid or powdered you will need to mix it with a few drops of water before testing it.

2) Test the chemicals with litmus paper.

3) Test each chemical with a few drops of universal indicator.

Litmus Indicator
Litmus indicator solution turns red in acidic solutions and blue in alkaline solutions. Litmus also comes in a paper form. Blue litmus paper will turn red in an acidic solution and remain blue when added to an alkali solution. Litmus does not tell you how strong the solution is.

Universal Indicator
A universal indicator shows us how strongly acidic or alkaline a solution is.
The universal indicator has many different colours changes, from red for strong acids to dark purple for strong bases. In the middle, neutral PH 7 is indicated by green.

Method: 

For Cabbage and Beetroot: 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 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 100ml of water into a 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.

This is the one that I did 
For the Cranberry Juice: Pour into a beaker and leave one side.

For the turmeric: Mix 1 teaspoon turmeric in a 100ml cup of alcohol.
Place in a small beaker and leave to one side.

This is how my experiment worked out: