Atomic weight of antimony

Thoso experiments were merely incidental to Cooke s researches on the atomic weight of antimony. 

Now, we consider 120 as the true atomic weight of antimony, for the reason that this number is in harmony with the following laws and rules —... 

Dc.xtcr in 1857 carried out some valuahlc work in Bunsen s laboratory to determine tho atomic weight of antimony. He carofully weighed out a small quantity of antimony and oxidised it with nitric acid, and finally heated tho residue until it was converted into ShjO.,. From 100 parts of Sh 0.j there were 79-28. (avcnige value) parts of Sh. Hence tho proportion ... 

The following independent methods for the determination of the atomic weight of antimony are given by Cooke —... 

In the years 1880-81 Cooke made his final determination of the atomic weight of -antimony. This time he used antimony trichloride and made the determination by the gravimetric method. The result obtained was 8b = 119-88. 

Summary.—The following is a summary of the different values assigned for the atomic weight of antimony as obtained by different workers and investigators employing different methods —... 

Cooke and Richards, Proc. Amer. Acad., 1887, xxiii, 149-76. Josiah Parsons Cooke (Boston 12 October 1827-12 September 1894), who was a pupil of Regnault, was professor of chemistry and mineralogy in Harvard (1850-94). He determined the atomic weight of antimony Proc. Amer. Acad., 1878, xiii, i), finding discrepant values. He wrote First Principles of Chemical Philosophy, Boston, 1869, revised, London, 1882, and The New Chemistry, 1873, 8 ed., 1884 Contributions from the Chemical Laboratory of Harvard College, 2 vols., Cambridge, Mass., 1877-89. 

The phase diagram for the copper-antimony system is shown on the next page. The phase diagram contains the intermetallic compound marked "X" on the diagram. Determine the chemical formula of this compound. The atomic weights of copper and antimony are 63.54 and 121.75 respectively. 

Halogen atoms in certain inorganic compounds may be replaced by fluorine by the use of antimony (III) fluoride without a catalyst. In other cases, varying amounts of different kinds of catalysts are required. For example, sometimes the addition of chlorine in the amount of 1 % of the antimony (III) fluoride will suffice. Molecules which are more difficult to fluorinate may require chlorine, bromine, or antimony(V) chloride in quantities amounting to as much as 5% of the weight of antimony (III) fluoride used. 

Phosphorus is a nonmetallic chemical element which, together with nitrogen, arsenic, antimony, and bismuth, comprise Group VA of the Periodic Table of the elements. Phosphorus has an atomic weight of 30.9738, and in all naturally occurring compounds is present as the stable isotope, P. Radioactive P has a half-life of... 

Antimony occupies atomic number SI in the periodic table, has an atomic weight of 121.7S, and is one of the amphoteric elements. Metallic antimony has a density of 6.684, a melting point of 630.5 C, and a boiling point of 1380 C. The element is resistant to acids (HF, HCl, HNO3, H2SO4) and to ammonia. It is only dissolved by hot concentrated sulfuric acid and by aqua regia. It is resistant to atmospheric conditions. 

The structures of antimony and bismuth correspond to that of gray arsenic. With increasing atomic weight the distances between adjacent atoms within a layer and between layers become less different, i.e. the coordination polyhedra deviate less from a regular octahedron. This effect is enhanced under pressure (cf. next section). 

The weight of oxygen in the solid product can be found by taking the total weight of the solid product and subtracting the amount of antimony and chlorine previously determined. This becomes 1.906 g solid product - 1.34 g antimony - 0.391 g chlorine = 0.175 g oxygen atoms in the solid product. 

Time-weighted average (TWA), 74 215 concentration, 25 372 exposure limit, for tantalum, 24 334 Time-Zero SX-70 film, 79 303, 305-307 Tin (Sn). See Lead-antimony-tin alloys Lead- calcium-tin alloys Lead-lithium-tin alloys Lead-tin alloys, 24 782-800. See also Tin alloys Tin compounds allotropes of, 24 786 analytical methods for, 24 790-792 in antimony alloys, 3 52t atomic structure of, 22 232 in barium alloys, 3 344, 4 12t bismuth recovery from concentrates, 4 5-6... 

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