The Densities of D2O-H2O Mixtures at 5 and 25°
The Densities of D2O-H2O Mixtures at 5 and 25°
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D2O-H2O 混合物在 5° 和 25° 时的密度
DOI：
10.1021/ja01870a063
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发表时间：
1939
影响因子：
15
通讯作者：
E. Swift
中科院分区：
文献类型：
--
作者：
E. Swift
Longsweet2已经表明，在25 ° C下，从混合时的体积变化的观点来看，H2O和D2O的混合物显然是理想的。他观察到的与理想状态的微小偏差是真实的还是由于实验误差引起的，可以通过重复他的实验来确定，这种重复的实验是以增加测量的灵敏度还是增加与理想状态的偏差的方式进行的。由于制备具有足够准确度的稀释液的固有困难，增加测量灵敏度是不切实际的，因此决定在较低温度下进行测量。根据Hildebrand的观点，偏离理想值的偏差通常随温度的降低而增加，因此，在5 ℃下观察到的偏差应比在25 ℃下观察到的偏差稍大一些。自从Longsworth的论文发表以来，文献中出现了一个新的纯D_（20）密度值。[4] Tronstad和Brun根据d202o的测量值计算出d2525的值为1.10750，而Selwood、Taylor、Hippie和Bleakney的计算值为1.10790。[5]最近在特龙斯塔德实验室中直接测量的d2hi为1.10764。这个新值重新计算了Longsworth的数据，
Longsworth2 has shown that at 25 mixtures of H20 and D20 are apparently ideal from the stand-point of volume changes on mixing. Whether the slight deviations from ideality he observed are real or due to experimental errors can be deter-mined by a repetition of his experiments carried out in such a manner as either toincrease the sen-sitivity of the measurements or to increase the deviations from ideality. Since it is impractical to increase the sensitivity of the measurements due to thedifficulties inherent in making the dilutions with sufficient accuracy, it was decided to carry out the measurements at a lower tempera-ture. According to Hildebrand3 deviations from ideality usually increase with decreasing tem-perature, and so the deviations observed at 5, for example, should be somewhat greaterthan those observed at 25.Since the publication of Longsworth’s paper, a new value of the density of pure D20 has appeared in theliterature. 4 The value calculated for d2525 by Tronstad and Brun from their meas-ured value of d202o is 1.10750, as compared with the value of 1.10790 obtained by Selwood, Taylor, Hippie and Bleakney. 5 A more recent direct measurement at 25 in Tronstad’s laboratory6 gives for d2hi 1.10764. This new value neces-sitates a recalculation of the data in Longsworth's