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概论铊的電化學性質對铊的極譜測定是很有利的。铊的標準電極電位和標準氧化還原電位等於-0.336和+1.22伏特。當電位趨近於-0.50伏特時,铊離子在滴汞電極止可逆還原。铊的半波電位殘乎與基本電解質(底液)的成份無關。在一切溶液中的铊極譜波就是隨着溶液中铊濃度的減少而又有所變化的很顯著的波階。可直接用極譜測定出的铊的最大濃度等於2—4毫克/毫升或1—2.10~(-5)克分子/立升。根据這些資料似乎可以作出這樣一个結論,即铊的極譜測定並不是一件困難的事。但是這個结論只有對於純的铊鹽溶液才是正確的。
Introduction The electrochemical properties of thallium are very favorable for the polarographic determination of thallium. Thallium standard electrode potential and the standard redox potential equal to -0.336 and +1.22 volts. When the potential approaches -0.50 volts, thallium ions are reversibly reduced at the drop mercury electrode. The half-wave potential of thallium is almost independent of the composition of the base electrolyte. The thallium polarographic wave in all solutions is a significant wave step that varies with decreasing concentrations of thallium in solution. The maximum concentration of thallium that can be determined directly by polarography is equal to 2-4 mg / ml or 1-2.10 ~ (-5) mol / liter. Based on these data, it seems that the conclusion can be drawn that thallium polarographic determination is not a difficult one. However, this conclusion is correct only for pure thallium salt solution.