In the course of the 19th century the idea that the different elements are constituted by different groupings or condensations of one primal matter - a speculation which, if proved to be well grounded, would imply the possibility of changing one element into another - found favour with more than one responsible chemist; but experimental research failed to yield any evidence that was generally regarded as offering any support to this hypothesis.
We now proceed to discuss the types of aliphatic compounds; then, the characteristic groupings having been established, an epitome of their derivatives will be given.
Examination of the absorption spectra of coloured compounds shows that certain groupings displace the absorption bands in one direction, and other groupings in the other.
It follows on this theory that all coloured substances contain either of the groupings or the former being a para-quinonoid, the latter an ortho-quinonoid.
Chemie, 24, p. 468) submitted the view that fluorescence was due to the presence of certain " fluorophore " groups; such groupings are the pyrone ring and its congeners, the central rings in anthracene and acridine derivatives, and the paradiazine ring in safranines.
Those containing the groupings CH 2 NO 2 and >CH NO 2) form metallic derivatives; for example, sodium salts, which according to A.
That state of mind was due to the fact that the groupings so recognized did not profess to be simply the result of scientific reasoning, but were necessarily regarded as the expressions of the " insight " of some more or less gifted persons into a plan or system which had been arbitrarily chosen by the Creator.
The commutative law for multiplication is directly illustrated; and subdivisions or groupings of the units lead to such formulae as (a+ a) (b + 0)=.
4 diketones, &c., according as they contain the groupings -CO CO-, -CO.
Constitution of the Diazo Compounds.-P. Griess (Ann., 1866, 137, p. 39) considered that the diazocompounds wereformed by theaddition of complex groupings of the type C 6 H 4 N 2 - to the inorganic acids; whilst A.
The invaders who have most affected the Berber race are the Arabs, but the two races, with a common religion, often a common government, with the same tribal groupings, have failed to amalgamate to any great extent.
The learner is to be led forward to the unknown by being made to hark back to more familiar groupings of the alphabet of nature which he is coming to recognize with some certainty.
Normally he thinks of what he calls phenomena no longer as psychological groupings of sensations, as " states of mind," but as things and events in a physical world howsoever constituted and apprehended.
Constellatus, studded with stars; con, with, and stella, a star), in astronomy, the name given to certain groupings of stars.
Work has been and is being done by the laborious methods here alluded to, and though the diversity of opinion as to the broader groupings of classification is still restricted only by the number of writers, we can point to an ever-increasing body of assured knowledge on which all are agreed.
The forty ancient counties, remnants of various historical groupings and partings, are occasionally bounded by rivers.
The aldo-ketenes are colourless compounds which are not capable of autoxidation, are polymerized by pyridine or quinoline, and are inert towards compounds containing the groupings C :N and C :O.