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Please tell me how a pH paper works. How does it decide whether the solution is an acid or a base on the basis of ions formed and how it can determine its concentration. How does it indicate an acid or a base?
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It's a piece of paper with one or a couple of these coated on it: https://en.wikipedia.org/wiki/PH_indicator
Indicators are dye molecules that change colour depending on the pH of a solution.
