Universal buffer soluttons and the association constant of veronal
Universal buffer soluttons and the association constant of veronal
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DOI：
10.1039/jr9310001456
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发表时间：
1931-01-01
期刊：
影响因子：
--
通讯作者：
Robinson, RA
中科院分区：
文献类型：
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作者：
Britton, HTS;Robinson, RA
近年来，可用于比色测定 pH 值的令人满意的标准缓冲溶液数量不断增加，被称为通用缓冲溶液的 5 类溶液不断增加。它们由强度递减的酸的混合物组成，通过连续中和，导致溶液的pa值从约2到12连续变化，pH的变化大约与添加的碱的量成比例。已经描述了两种含有磷酸、乙酸或聚乙酸和硼酸的缓冲溶液（Prideaux, Proc. Roy. Xoc., 1916, 92, A, 463；Prideaux 和 Ward, J., 1924, 125, 426），其 pH 范围为 2-12，但本作者已经表明（本卷，第 458 页）含磷酸、苯乙酸和硼酸的缓冲溶液的pH值与中和度的关系不是直线而是波动的，使用线性插值公式可能会导致pH值误差高达0.2个单位。该通讯包含对磷酸、乙酸和硼酸的原始混合物的更详细研究，还描述了一种新的通用缓冲溶液，该缓冲溶液在相当大的中和过程中给出了 pH 值的严格线性变化。这是通过事实成为可能的（参见 Kolthoff，“Gebrauch der Farbenindikatoren”，1923 年，第 163 页；
THE large number of satisfactory standard buffer solutions available for the colorimetric determination of pH values has been augmented in recent years by 5 class of solutions known as universal buffer solutions. These consist of mixtures of acids of diminishing strength, by the successive neutralisation of which the pa values of the solutions are caused to vary continuously from about 2 to 12, the change in pH being approximately proportional to the amount of alkali added. Two such buffer solutions containing phosphoric, acetic or plienylacetic, and boric acids have been described (Prideaux, Proc. Roy. Xoc., 1916, 92, A, 463; Prideaux and Ward, J., 1924, 125, 426), having a pH range of 2-12, but the present authors have shown (this vol., p. 458) that the graph of the p H of the buffer solution containing phosphoric, phenylacetic, and boric acids against the degree of neutralisation is not a straight line but is undulatory in character, and that the use of a linear interpolation formula may lead to errors of as much as 0.2 unit in pH. This communication contains a more detailed study of the original mixture of phosphoric, acetic, and boric acids and also a description of a new universal buffer solution which throughout a considerable portion of its neutralisation gives a rigidly rectilinear change in pH. This has been made possible through the fact (see Kolthoff,“Gebrauch der Farbenindikatoren,” 1923, p. 163;