Universal indicator test on a lemon. A piece of universal indicator paper held against a freshly-cut face of lemon. The change of colour from yellow t

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

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Size: 4181px × 4181px
Photo credit: © Science Photo Library / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: acid, acidity, analysis, basic, chemical, chemistry, citrus, confirmation, demonstration, experiment, food, foodstuff, fruit, indicator, laboratory, lemon, paper, ph, red, school, science, simple, test, universal, yellow