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Indicators for Acids and Bases



Thomas J. Bruno, Paris D. Svoronos


The following table lists the most common indicators together with their pH range and colors in acidic and basic media. Since the color change is not instantaneous at the pKa value, a pH range is given where a combination of colors is present. This pH range, which varies between indicators, generally falls between the pKa with a spread or uncertainty of 1 pH unit. All solutions are either aqueous or ethanol/aqueous (% ethanol, vol/vol) [1-4]. Reference 4 provides additional solution properties that are related to buffer and solvent properties, and reference 5 lists the exact quantities needed for the indicator’s solutions.
CRC Handbook of Chemistry and Physics - 93rd edition
Publisher Info
CRC Taylor Francis, Boca Raton, FL


Bruno, T. and Svoronos, P. (2012), Indicators for Acids and Bases, CRC Taylor Francis, Boca Raton, FL (Accessed March 4, 2024)
Created June 22, 2012, Updated February 19, 2017