THE THERMAL DISSOCIATION OF CALCIUM CARBONATE.
THE THERMAL DISSOCIATION OF CALCIUM CARBONATE.
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DOI：
10.1021/ja01926a006
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发表时间：
1910-08
影响因子：
15
通讯作者：
J. Johnston
中科院分区：
文献类型：
--
作者：
J. Johnston
布里尔，1波特2和扎夫里耶夫。8.最近，B。H. Riesenfeld 4讨论了这些作者的数据。他的结论是，由于在测量压力或温度，或两者的错误，前三个作者的数据是完全不可信的，并建立了一个涉及经验公式来表达Zavriev和Pott的平均结果。Pott在600-900 ℃的温度范围内进行了四个系列的测量;然而，这些测量绝不是那么一致，因为可能希望，e。例如，在一个实施例中，对于892，他发现压力从593毫米变化到776毫米。尽管如此，通过他的点中间画出的曲线与代表扎夫里耶夫的结果的曲线大致一致，扎夫里耶夫的结果在数量上相对较少，但它们之间更一致。从这两个作者的结果可以看出，解离点（即：例如，二氧化碳压力为一个大气压时的温度）接近910。这个值由Riesenfeld的特殊实验证实，他重新测定了碳酸盐在纯二氧化碳气氛中加热时发生重量损失的温度。此外，他还指出，实际上排除了氧化钙在碳酸盐中形成固溶体的可能性，反之亦然，而扎夫里耶夫则表明不存在碱性碳酸盐。因此，现在已经明确证明，碳酸钙的分解根据方案CaCO 3 CaO+ CO2进行，并且仅根据该方案进行。因此，结果的差异完全是由于物质温度测量的误差或压力误差造成的，而这些误差或是由于没有达到平衡条件，或是由于水蒸气或其它能产生压力的杂质的存在。
Brill, 1 Pott2 and Zavriev. 8 Quite recently, B. H. Riesenfeld4 has dis-cussed the data of each of these authors. He concludes that, owing to errors in the measurement of pressure or of temperature, or of both, the data of the first three authors are altogether untrustworthy, and sets up an involved empirical formula to express the mean results of Zavriev and Pott. Pott made four series of measurements over the temperature range 600-900; these, however, are by no means so concordant as might be wished, e. g., for 892 he found pressures whichvaried from 593 mm. to 776 mm. Still, a curve drawn through the midst of his points coincides approximately with that which represents the results of Zavriev, which are relatively few in number but more concordant among themselves. From theresults of either author it follows that the dissociation point (i. e., the temperature at which the pressure of carbon dioxide is one atmosphere) is close to 910. This value was confirmed by special ex-periments made by Riesenfeld, who determined anew the temperature at which a loss of weight occurred when the carbonate was heated in an atmosphereof pure carbon dioxide. He showed, moreover, that the possibility of formation of solid solutions of calcium oxide in the car-bonate and vice versa is practically excluded, while it was shown by Zavriev that no basic carbonate exists. It has therefore now been definitely proved that the dissociation of calcium carbonate proceeds according to the scheme CaC03 CaO+ C02, and to that scheme solely. The discrepancies in the results are thus to be attributed entirely eitherto errors in themeasurement of the tem-perature of the substance, or to errors in the pressure, due either to the fact that equilibrium conditionshad not been attained or to the presence of water vapor or of some other impurity capable of developing a pres-