Unitary Theory


Also found in: Dictionary, Wikipedia.

Unitary Theory

 

a system of views in 19th-century chemistry based on the concept that the molecule is a unified whole made up of atoms of the chemical elements. The unitary theory took shape in the 1830’s and 1840’s in the works of J. Dumas, A. Laurent, and, in particular, C. Gerhardt, who set forth the theory in his Introduction to the Study of Chemistry According to the Unitary System (1848; Russian translation, 1859). The theory challenged the generally accepted dualistic theory of J. Berzelius, which regarded chemical compounds as combinations of two distinct constituents bearing opposite electrical charges. The inability of this theory to account for reactions involving the substitution of chlorine for hydrogen in organic compounds was one of the principle reasons for the theory’s abandonment.

The historical significance of the unitary theory lies in its clear distinction between the concepts of atom, molecule, and equivalent and its introduction of Avogadro’s law and “two-volume” formulas, that is, formulas using the H2 molecule as the unit of comparison. In addition, the theory made possible correct values for many elements and corrections of formulas for the elements’ compounds. The basic principles of the unitary theory were accepted in 1860 at an international congress of chemists held in Karlsruhe.

REFERENCE

Faershtein, M. G. Istoriia ucheniia o molekule v khimii (do 1860 g.). Moscow, 1961. Pages 243–66, 283–352.

S. A. POGODIN

References in periodicals archive ?
One might think that this "fact" would preclude any originalist from subscribing to a unitary theory of the removal power, unless they reach for Tillman's escape hatch.
Nicknamed "executive power on steroids" (Epstein 2006), the unitary theory of executive power emerged in the 1980s in the Justice Department's Office of Legal Counsel under President Reagan.
12) Thereafter, a lengthy series of articles appeared debating the merits of the unitary theory (Calabresi and Prakash 1994; Lawson 1994; critics include Flaherty 1996; Greene 1994; Kinkopf 1998; Lessig and Sunstein 1994).
Their analogy to the controlled-group mechanics of Section 41 is inapposite, however, without being guided by unitary theory.
Throughout this unraveling of LD history, Coles shows that as each new explanation failed to support a unitary theory of neurological dysfunction, a new one was found to replace it.
TACA might also be viewed as an early example of imposing jurisdiction under the unitary theory.
In her unitary theory of intentionality as the matrix for healing, Zahourek (2002), contends that healing is "a dynamic, transformational and ongoing process in which individuals" experience a shift in their being and feel they have significantly changed" (p.