A Derivative Spectrometric Method for Hydroquinone Determination in the Presence of Kojic Acid, Glycolic Acid, and Ascorbic Acid

Figure 4

Overlaid spectra of the studied compounds in the absence (solid lines) and in the presence (dashed line) of K₂Cr₂O₇ in 1 mol·L⁻¹ sulfuric acid; every compound has the same concentration (2 × 10⁻⁴mol·L⁻¹).

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