Abstract—Aims: Effect of pH on polarographic waves of ascorbic acid were studied by recording polarograms of ascorbic acid solution, between 0 to 400 mV at different pH (0.065 to 9.6) using 0.008% solution of gelatin and 0.05 M potassium hydrogen phthalate buffer (containing 0.25% oxalic acid) as maxima suppressor and supporting electrolyte respectively.
Methods: Ascorbic acid is strong reducing agent and produces an anodic wave which shifts with pH. There is no significant change in height of wave with change in pH from 2.25 to 4.85.
For determination of ascorbic acid pH 4.0 is chosen. Ascorbic acid present in synthetic sample is determined by calibration, external standard addition and internal standard addition methods. The results obtained are in good agreement with the quoted values.
Result: The number of electrons taking part in the reversible reaction is found to be 2. The half-wave potential is found to be independent of the ascorbic acid concentration
Index Terms—Ascorbic acid, calibration method, external standard addition method, internal standard addition method, polarographic determination
Swaroopa Rani N. Gupta is with the Department of Chemistry, Brijlal Biyani Science College Amravati, Maharashtra, India (e-mail: swargupta@yahoo.com)
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Cite: Swaroopa Rani N. Gupta, "Development of Calibration and Standard Addition Polarographic Determination of Ascorbic Acid," International Journal of Chemical Engineering and Applications vol. 6, no. 2, pp. 86-90, 2015.
