Potentiometric Determination of Ascorbic acid,Malonic acid and Resorcinol Using Sulphide and Cyanide Ion-Selective Electrodes Compared with Platinum Electrode.


A new potentiometric method was adopted for the determination of ascorbic acid , malonic acid and resorcinol using iodine (dissolved in glacial acetic acid) as oxidant . The liberated iodide was monitored using sulphide and cyanide ion-selective electrodes compared with platinum electrode . The potential changes were sufficiently sharp (in the range of 280-300mV/0.1ml) for establishing the end points over a range of 0.001-0.100M of these reductants . The method was found accurate for determination of these reductants individually and in their mixtures .