Prout

A R, D P Dolata and K Prout 1990. Automated Conformational Analysis and Structure Generation Algorithms for Molecular Perception. Journal of Chemical Information and Computer Science 30 316-324. 

N. M. Prout and J. S. Moorhouse, eds.. Modem Chlor—Alkali Technology, Vol. 4, Elsevier AppHed Science, 1990. 

Curious products isolated by Bailey and Evans from the reaction of benzotrisfuroxan with triphenyl phosphine have been examined by X-ray crystallography by Cameron and Prout. The structures (44-46) were determined.A molecular complex of trialkyl phosphate with benzotrisfurazan is formed using a trialkyl phosphite as reducing agent. 

Paper nine is another one that appeared in American Scientist. In it I took a philosophical look at two important ideas that contributed to the evolution of the periodic system. These two ideas are Prout s hypothesis and the notion of triads, which was the subject of paper eight. Both hypotheses are interesting because they were extremely productive even though they both turned out to be refuted some time later. The fact that this should happen lends some support to the views of Karl Popper who always claimed that refutability was the all important aspect of good hypotheses and theories and not whether they turn out to be correct or not.23 For Popper, all that we really have is tentative theories and not theories that last forever. 

Prout s hypothesis that the atoms of all elements were composites of hydrogen. Further, Mendeleev was particularly fond of emphasizing that smooth curves should not be drawn through the points representing numerical data on the elements, since such curves would imply continuity instead of strict individuality. 

It is probably fair to say that much time was wasted by other researchers in trying to uncover triads where they simply did not exist. Some pioneers, including Mendeleev, made it a point to turn their backs on numerical approaches such as Prouts hypothesis and the search for triads. This attitude certainly seems to have paid dividends for Mendeleev in that he made progress where others had failed to do so. 

The problem with triads, as well as the other important numerical hypothesis due to Prout, is easy to discern in retrospect. It is simply that atomic weight, which both concepts draw upon, is not the most fundamental quantity that can be used to systematize the elements. The atomic weight of any element depends on the particular geological origin of the sample examined. In addition, the atomic weight of any particular element is an average of several isotopes of the particular element. 

Mendeleev went to some length to distance himself from the use of numerical relationships such as Prout s relationship and the notion of triads. However, it is quite clear that many of his predictions of the properties of new elements involve the notion of triads. The triads he considered were sometimes vertical, or horizontal, or at times the combination of both vertical and horizontal triads. 

A little earlier, in 1815, the London based physician, William Prout, proposed another general principle. In a few papers, which he published anonymously, Prout wrote that the fact that the atomic weights of many elements seemed to be integral multiples of the weight of hydrogen suggested that all... 

This is known as the Prout—Tompkins equation and has found application to many systems, in addition to the thermal decomposition of potassium permanganate [465] with which it is often associated. The kinetic behaviour of silver permanganate was somewhat different and in a variation of... 

Fig. 2. Reduced time plots for the Avrami—Erofe ev equation [eqn. (6)] with n = 2, 3 and 4 and tT = (t/ta.g) the Prout—Tompkins expression [eqn. (9)] is included as the broken line.

Reference to the decomposition of KMn04 has already been made in the discussion of chain branching reactions (Chap. 3, Sect. 3.2) in which the participation of a highly reactive intermediate was postulated. This work provided a theoretical explanation of the Prout—Tompkins rate equation [eqn. (9)]. Isothermal decomposition in vacuum of freshly prepared crystals at 473—498 K gives symmetrical sigmoid a time curves which are described by the expression... 

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