Litmus test on a lemon. A piece of blue litmus paper held against a freshly-cut face of lemon. The change of colour from blue to red means that the le

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Litmus test on a lemon. A piece of blue litmus paper held against a freshly-cut face of lemon. The change of colour from blue to red means that the lemon must be acidic. Lemons, like all citrus fruits, contain citric acid.

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Photo credit: © Science Photo Library / Alamy / Afripics
License: Licensed
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Keywords: acid, acidity, analysis, basic, blue, chemical, chemistry, citrus, confirmation, demonstration, experiment, food, foodstuff, fruit, laboratory, lemon, litmus, paper, ph, red, school, science, simple, test