Valency, auxiliary secondary

The formation of sulphuric and chlorosulphuric acids by the union of sulphur trioxide with water and hydrogen chloride respectively is brought about by the secondary valencies as indicated in the schemes 03S+0H2=03S. . . OH2 and 03S+C1H=03S. . . C1H. When one of the reacting molecules contains douhle-linked atoms, the auxiliary valencies may not he sufficiently strong to preserve the integrity of the new mol., and, the atoms of the addition product may be rearranged. For example, this is the case with sulphur trioxide. Thus ... 

The question of nomenclature is an important one and must be considered in this connection. Werner introduced certain terms in the development of his theory involving main and auxiliary (or secondary) valences, and these terms are useful. The consideration of a group in a molecule in which the atoms react as a unit, as the inner zone or sphere, and another group as the outer zone is used by Werner, the former to denote the group consisting of the central atom combined with other atoms or groups by... 

Note that the correct relation between coordinate valency and Werner s auxiliary or secondary valency (p. 468, col. 1, para. 3 up) is secondary valency = coordinate valency - primary valency used in coordination. ... 

It is true of course,that macroscopic chunks of matter are quite extremely close to electroneutrality.The Nebenvalenz (secondary or "auxiliary" valency) of a given element in a definite primary valency is the (preferred) number N of immediate-neighbor ligating atoms X. 

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