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PC2139
Price: $5.20
Phenolphthalein is a dye used as an acid–base indicator that is colorless in acidic or neutral solutions and turns bright red-violet as it becomes basic. In strongly basic solutions, the red color slowly fades and it again becomes colorless. With the technology-based Kinetics of Dye Fading: Technology and Graphical Analysis—ChemTopic™ Lab Activity, use colorimetry and graphical analysis to determine how the rate of the phenolphthalein fading reaction depends on the concentration of the dye. The absorbance of the red solution will be measured at specific time intervals.