Typically in the sophomore level analytical chemistry laboratory, strong acid solutions are standardized against sodium carbonate with bromocresol green as the overwhelming indicator of choice in the literature. The endpoint occurs between pH 4 and 5 with a color change of light blue to pale green. The transition between blue and green is often difficult to detect and does not allow the desirable level of accuracy and precision to be obtained readily. Often novice chemists titrate beyond the endpoint to an irreversible yellow solution. However, bromocresol green remains the overwhelming indicator of choice in the chemical literature and not methyl red. Preliminary studies indicate methyl red provides superior results. The statistical data (mean, standard deviation, Q-test and t-test) comparing bromocresol green with methyl red for standardization of hydrochloric acid solution will be presented herein.
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