Popis: |
Ion-selective chalcogenide disc electrodes have been developed which are responsive to cations such as silver, lead, chromium(III), nickel, cobalt(II), cadmium, zinc, copper(II) and manganese(II) ions. Each was prepared by using the corresponding metal chalcogenide with silver sulphide. An electrode was assembled with both a compacted and a sintered disc. The sintered electrodes were more sensitive and stable than the compacted ones. Response to silver ion was 59.5 mV pAg , to lead, nickel, cadmium, zinc and copper(II) 29.5 mV pM and to chromium(III) 20 mV pM . Cobalt(II) and manganese(II) electrodes had a non-Nernstian response of 25 mV pM . Both selenides and tellurides can be used for potentiometric determination, but the manganese(II) electrode serves as an analytical tool only when the disc consists of manganese(II) telluride and silver sulphide. |