New measurements have been made of the refractivities a t 20°, and the parachors of aliphatic aldoximes, ketoximes, and ketoxime O-alkyl ethers, NN-dialkylhydrazines, aliphatic ketazines, p-mono-and F-di-alkylaminopropionitriles, P-alkoxypropionitriles, dialkyl azodiformates and dialkyl carbonates, and the contributions of the :N*OH, :NO, N-NH,, :N-N:, NH, N (tertiary), N:N, and CO, groups, and of 0 (from alkoxypropionitriles) have been evaluated. The bond refractions, as well as the bond parachors and the bond-refraction coefficients, have been computed for a large number of links with the aid of the experimental data given in this and previous papers of this series. The bond constants of several links have been deduced by a number of independent methods, and the results are in satisfactory agreement. The comprehensive table of bond refractions and bond parachors may be employed for the computation of " theoretical " refractions and parachors. The bond-refraction coefficients permit of the calculation of the refractive index (nio) of a liquid compound from its chemical formula.The structures of the esters of oxy-acids and of related compounds are discussed.THE determination of atomic, group, and structural parachors and refractivities has been extended to a number of series of nitrogen-containing compounds (compare Eisenlohr, 2. physikal. Chem., 1912,79,412). New measurements of the densities and surface tensions over a range of temperatures as well as the refractive indices at 20" for the c, D, F, and G' lines have been made and the constants calculated as in previous papers of this series. TABLE 1. Values for the :N*OH group from aldoximes artd ketoxiines.
Analysis of the refraction data in the literature for liquid tin, silicon, lead, germanium and mercury compounds, using the fundamental bond refractions of Vogel (1948) has yielded a system of bond refractions for these five elements. These replace and extend inter alia the bond refractions for tin compounds of West and Rochow (1952) and for silicon compounds of Warrick (1946), which were based upon the older constants computed by Denbigh (1940).
The nickel and cobalt salts of the aliphatic acids studied decompose by primary cleavage into metal oxide and anhydride. The anhydrides then suffer extensive pyrolysis and the ultimate products include metal, metal oxide, carbide and a mixture of vapours (acids, ketones, carbon dioxide, carbon monoxide and hydrogen). The decomposition of nickel acetate in particular provides a good method of preparing nickel carbide Ni3C. The oxide formed from the slow air decomposition of nickel acetate is possibly a useful oxide catalyst. A new modification of cobaltous oxide is formed in good yield from the acetate.
SCIENTIFIC AMERICAN SUPPLEMENT No. 845. 13505 of ms viva which the sun pours out yearly upon every acre of the earth's surface, chiefly in the form of heat, is 800,000 horse power. * Of this mighty supply of en ergy, a flourishing crop utilizes only 3,200 horsepower, so that the energy wasted per acre of land is 796,800 horse power. We talk loudly of the importance of utilizing the refuse of our manufactures; but what is the value of alkali waste, of furnace slags, of coal tar, or of all of them together, compared to the loss of 796,800 horse power per acre?
The preparation and properties of gels of boron phosphate in concentrared sulphuric acid and oleum are described. Boron arscnate gels are also briefly discussed.The usual method for thc production of gels containing sulphuric acid is the formation of a silidc aad gel in sific by the action of sulphuric acid upon an admixed solution of sodium silicate. This has been particularly useful for the more dilute solutions of sulphuric acid,l but there are practical difticulties if a gel of high sulphuric 2cid content or an oleum gel is required.Schulze? in 1933 showed that the so-called boron phosphate, BPO,, possessed a cristobalite structure in which the silicon atoms are replzced alternately by boron and phosphorus atoms, and it therefore follows that under suitable conditions it may be possible to create a boron phosphate gel in sulphuric acid in a similar manner to that in which silicic acid gels are obtained. The conditions under which this takes place form the subject of the present communication.The isomorphous boron arsenate BAsO, has also been obtained as a gel in concentrated sulphuric acid.3 I ExperimentalMaterink-Thc sulphuric x i d and boric acid were of laboratory reagent quality. Phosphoric acid was of B.P. grade (density Gel forrnution in coilcentrated srdplrrrric acid.-The boric acid was dissolved in a given volume of concentrated sulphuric acidby gentle warming; and the calculated quantity of phosphoric acid mixed with the samc volume of concentrated sulphuric acid. Equal volumes of the LWO solutions were thcn &ed at the temp-rarures shown, with the results indicated in Table I. General properties o/ dit gels.-(r) Equimolecular proportions of thc two acids gave the best gels, but the quantities could be varied within wide limits (& 30%) without seriously affecting gel formation for the I;IOO and more concentrated gels.(ii) The firmness increased with the concentration.(iii) Gels formed at 25' were faintly opalescent, while if formed at 100' they were more strongly opalescent.(iv) All the gels displayed slight syneresis, but there was link indication of thixatropic properties.(v) Addition of small amounts of water to the 1/10, 1/20, and I!SO gels followed by a minimum of stitring caused a rapid breakdown of the gel structure and the formation of a white viscous precipitate. More water then gave a char solution.For gels of lower concentration, addition of water yielded a clear solution immediately, without separation of any intermediete solid phase.(vi> Heating the 1/400 gel to IOO' caused breakdown in a few minutes, but the other gels all withstood long periods of heating at 100' or higher without breakdown, though they soon became turbid.(vii) At-mom temperatures, the gels remain unchanged for several months, exccpt for a very slight increase in opalescence.Effect of etariotion in cotrcentrution of srdplttiric acid.-Instead of using concentrated sulphuric acid as the gdhg medium it was found possible to use either o h m or diluted acid (down to a lower limit of approx. 82% acid). With increasing water ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.