【摘要】 <正> 难溶化合物组分络合平衡的研究是比较困难的,因为溶解度很小,在不产生沉淀的稀溶液中测定其平衡组分的方法必须足够灵敏和准确。截至目前为止,只是对少数这类物质的稳定常数作过测定。在所报导的离子选择电极测定法中电极的校正均采用分析浓度校正曲线,相对于金属离子浓度,配位体为不足量,因此只能测得一级络合物的稳定常数。由于研究络合平衡时所要求测定的正是自由离子浓度,因此本文提出用铅离子缓冲溶液作铅电极的校正曲线测定草酸铅和硫酸铅络合物的稳定常数。该法容许相对于铅离子浓度配位体大更多还原

【Abstract】 The method given are suitable for determining the complex stability constant of lead oxalate or lead sulfate under the excess of oxalate or sulfate. The foundational equation is(10^E/s-1)/C_A=β₁+C_Aβ₂ Where C_A is analytical concen tration of oxalate or sulfate. The response slope of lead electrode in lead ion buffer solutions is considered as the response slope S in the foregoing equation、A straight line is obtained from(10_E/S—1)C_A vs C_A plot, the intercept is β₁ and the slope is β₂. The logβ₁ and logβ₂ determined are 4.30±0.06 and 6.72±0.06 for lead oxalate complex respectively. The experiment proves that Pb²⁺ with SO₄^2-does not form any Pb（so₄）₂^2- except PbSO₄. The stability constant of lead sulfate complex, K_phso4,equals to 591±46.更多还原