Theory A set of assumptions put

Model (theory) a set of assumptions put forth to explain the observed behavior of matter. The models of chemistry usually involve assumptions about the behavior of individual atoms or molecules. (1.3)... 

Millimeters of mercury (mmHg) a unit of pressure, also called a torr, 760 mm Hg = 760 torr = 101,325 Pa = 1 standard atmosphere. (5.1) Mineral a relatively pure compound as found in nature. (21.8) Model (theory) a set of assumptions put forth to explain the observed behavior of matter. The models of chemistry usually involve assumptions about the behavior of individual atoms or molecules. 

Theory (model) a set of assumptions put forth to explain some aspect of the observed behavior of matter. 

In a series of papers published in 1953, Pariser, Fumi, and Parr16 w 54>55 put forward a set of simplifying assumptions which together constituted a semiempirical theory for the interpretation of aromatic hydrocarbon spectra. 

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