Tester pH paper, known as litmus paper, is a special scientific tool you can use to test whether a liquid is an acid or a base. The paper is covered in dyes that interact with the liquid you're testing and change color. The litmus paper can turn varying shades of red or blue depending on whether the item in question, such as a glass of water, is acidic or basic.
Litmus Paper and Water
Litmus paper generally comes in two colors, red and blue. If you dip both the red and the blue litmus paper in water and their colors don't change, the water in question is neutral. However, if you dip blue litmus paper in the water and it turns a pink or red hue, the water you are testing is acidic. On the other hand, if you dip red litmus paper in water and it turns a shade of blue, you can conclude that the water is basic.
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