Instrument
The basic apparatus for polarographic analysis is given in Fig. The commonl y used polarographic cell has an external reference electrode and is the H-cell. It consists of two compartments, one containing the solution to be studied and the other containing reference electrode. These compartments are separated by a cross-member filled with 4% agar-saturated potassium chloride gel, which held in place by a medium-porosity sintered disc. The second compartment is the solution compartment into which DME is inserted and this has N2 inlet and outlet provision.
This simple recording polarogram unit has a potentiometer, 'P' by which any emf upto 3 Volts may be gradually applied to the cell. 'R' is a pen recorder and 'V' is voltmeter.
(Photo of Original Polarograph used by Heyrovsky obtained from Institute of Physical Chemistry, Praha, Czech-Republic is given below).
