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Certain organic substances change color in dilute solution when the hydronium ion concentration reaches a particular value. For example, phenolphthalein is a colorless substance in any aqueous solution with a hydronium ion concentration greater than 5.0 × 10−9 M (pH < 8.3). In more basic solutions where the hydronium ion concentration is less than 5.0 × 10−9 M (pH > 8.3), it is red or pink. Substances such as phenolphthalein, which can be used to determine the pH of a solution, are...

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Should the Prader 3-mL orchidometer bead change colour?

Petur B Juliusson^1,2,3, Mathieu Roelants⁴

¹Department of Health Registry Research and Development, Bergen, Norway.

Acta Paediatrica (Oslo, Norway : 1992)

|September 5, 2023

Summary

No abstract available in PubMed .

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