What you need
Red Cabbage Indicator – made by boiling chopped red cabbage in water for 10 minutes
White filter paper
Vinegar/baking soda/lemon juice to test
Dip a piece of filter paper into the red cabbage indicator and leave to dry.
Once dry, drop the solutions to test onto the paper and watch as the colour changes
Indicators and the pH scale
Solutions can be acidic, alkaline or neutral:
- an acidic solution is when an acid is dissolved in water
- an alkaline solution is when an alkali is dissolved in water
- solutions that are neither acidic nor alkaline are neutral.
Pure water is neutral.
An indicator is a substance that changes colour when added to an acidic or alkaline solution.
In a laboratory either Litmus or Universal Indicators are used. Litmus can only tell us if a substance is an acid or alkali while Universal Indicator tells us how strong the acid or alkali is.
A craft stick or lolly stick chain reaction is a brilliant example of potential and kinetic energy. As you weave
These easy squeezy bottle rockets are great fun to make and a brilliant introduction to forces, in particular Newton’s Third
Original article and pictures take http://www.science-sparks.com/2016/07/29/how-to-make-ph-indicator-test-strips/#_a5y_p=5632080 site