Abstract

Interaction between the systems containing cobalt(II) or nickel(II) chlorides and 2-thiobarbituric acid (C₄H₄N₂O₂S, H₂L) was examined by spectrophotometry and pH-metry at pH < 4, I = 0.1 (NaCl) and T = 20°C. The compositions and the overall stability constants (log β₁₁) of protonated complex species were determined: [CoHL]⁺ (3.69 ± 0.04), [NiHL]⁺ (3.68 ± 0.08), and [M(HL)₂]. The compositions of the Co(C₄H₃N₂O₂S)₂ · 4H₂O and Ni(C₄H₃N₂O₂S)₂ · 5H₂O salts isolated from the studied systems were confirmed by different physicochemical methods; their solubility constants (log K_S) were calculated to be –12.82 ± 0.22 and –12.30 ± 0.10, respectively. A spectrophotometric technique was developed for determining thiobarbiturate ion in aqueous solutions. This technique is based on the absorbance of iron(III) thiobarbiturate complex [FeL]⁺ and can be recommended for analytical chemists and pharmacists.

中文翻译：

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含2-硫代巴比妥酸的钴（II）和镍（II）化合物

摘要

含钴（II）或镍（II）氯化物和2-硫代巴比妥酸（C系统之间的相互作用₄ ħ ₄ Ñ ₂ ö ₂ S，H ₂是在pH <4通过分光光度法和pH metry检查L），我= 0.1（NaCl）和T = 20°C。的组合物和整体稳定性常数（日志β ₁₁质子化复合物种）测定：[科尔] ⁺（3.69±0.04），[NIHL] ⁺（3.68±0.08），和[M（HL）₂ ]。Co（C ₄ H ₃ N ₂ O ₂ S）₂ ·4H的组成从研究体系中分离出₂ O和Ni（C ₄ H ₃ N ₂ O ₂ S）₂ ·5H ₂ O盐，用不同的理化方法进行了确认；其溶解度常数（log  K _S）经计算分别为–12.82±0.22和–12.30±0.10。开发了用于测定水溶液中硫代巴比妥酸根离子的分光光度技术。该技术基于硫代巴比妥酸铁（III）铁（FeL）⁺的吸光度，可推荐给分析化学家和药剂师。