Things Required:
1/2 cup of berries (blackberries, blueberries or strawberries)
Small strips cut from white construction paper
A small bowl
A fork
Water
A teaspoon
Paper towels
Directions:
Remove any stems and place the berries in a bowl. Crush the berries with the fork until they look like jam. Add a little water to thin the juice. Dip the paper strips in the juice and spoon the juice over them until they are well coated. Slide the strips between your thumbs and finger to remove the pulp. Place the strips on paper towels to dry. When they are dry, pick off any big pieces of pulp or berry skins you missed and your litmus paper is ready for use.
What Do The Colour Changes Mean?
Purple blackberry litmus turns pinkish-red in acids and deep purple in alkali compounds, or bases. These strips work best for litmus testing, for they show the most change.
Purple blueberry litmus turns reddish-purple in acids and light bluish-purple in bases.
Pink strawberry (although not so noticeable as the other two) turns bright pink in acids and light pinkish-blue in bases.
Thoroughly confused? Not to worry! We can tell you how to remember this easily: the paper that has more red in it is reacting to acids, while the paper that has more blue in it is reacting to bases.
