Abstract:
The heat capacity and entropy of elementary substances are considered in this work as a thermodynamic basis of geochemical systematics of the respective elements. According to the Oddo–Harkins rule, they are divided into even and odd groupings based on their abundance. In order to justify this division, the mean composition of carbonaceous chondrites (C) that makes up only 2–5% of the total chondrite dips [2] has been used in [1]. The predominant ordinary chondrites are divided into approximately equal low-Fe (L) and high-Fe (H) varieties. This subdivision reflects a bimodality of the dominating group of meteorites [3].