Univalent Compounds of Zinc

Formation of the Group-IB or -IIB-Group-IB or -MB Metal Bonds 8.2.3. In Univalent Compounds of Zinc and Cadmium... 

Goldberg, R. N., (1980b). "Evaluated Activity and Osmotic Coefficients for Aqueous Solutions Bi-univalent Compounds of Zinc and Cadmium, and Ethylene bis(trimethylammonium) Chloride and Iodide," manuscript in review. 

Z5. Goldberg, R.N., "Evaluated activity and osmotic coefficients for aqueous solutions Bi-univalent compounds of zinc, cadmium, and ethylene... 

The brittleness of these intermetallic compounds suggests an electronic structure involving a filled Brillouin zone. It was pointed out by Ketelaar (1937) that the strongest reflection, that of form 531, corresponds to a Brillouin polyhedron for which the inscribed sphere has a volume of 217 electrons per unit cube, which agrees well with the value 216 calculated on the assumption that the sodium atom is univalent and the zinc atoms are bivalent that is, calculated in the usual Hume-Rothery way. It has also been... 

The apparent anomaly between mercury and the lighter elements of transition group 2. in that mercury regularly forms both univalent and divalent compounds, while zinc and cadmium do so very rarely, is partly under mm id from the observation that mercury III salts ionize even in the gaseous late to Hg.. rather than Hg Evidence for this double ion is provided by its Hainan spectral line, by the lineal CI-Hg-Hg-CI units in crystals or mercury It chloride, and by the cml of incrciirytll nitrate concentration cells The anomaly is fuitlicr removed by the obsetv.ttioii that cadmium also forms a (much less stable) diatomic ton Cdj T eg., ill Cd.-lAICL) . 

Apart from antimony, there are other good promoters of the direct synthesis of methylchlorosilanes, which increase the yield of dimethyldichlorosilane, such as arsenic and zinc chloride. If it is necessary to increase the yield of alkylhydridechlorosilanes, one should use univalent copper chloride, cobalt, and titanium. The addition of tin or lead into contact mass increases the yield of dimethyldichlorosilane up to 70% the yield of ethyldi-chlorosilane is increased to 50-80% when contact mass receives 0.5-2% of calcium silicide (Ca2Si). In the synthesis of phenylchlorosilanes effective promoters are zinc, cadmium, mercury or their compounds. In particular, the introduction of zinc oxide (up to 4%) into contact mass may increase the diphenyldichlorosilane content up to 50%, and the introduction of a mixture of zinc oxide and cadmium chloride, even up to 80%. 

It was pointed out by Hume-Rothcry 4 in 1926 that certain interns etallic compounds with close]y related structures but apparently unrelated stoichiometric composition can be considered to have the same ratio of number of valence electron to number of. atoms,. For example, the j8 phases of the systems Cu—Zti, Cu—-Alv and Ou -Sn are analogous in structure, all being based on the -4.5 arrangement their compositions correspond closely to the formulas CuZn, CusAl, and CtttSn. Considering copper to be univalent, zinc bivalent, aluminum trivalent, and tin quadrivalent, we see that the ratio of valence electrons to atoms has the value f for each of these compounds ... 

Valency and Ions.—Copper is usually considered to exhibit univalency in the cuprous compounds and bivalency in the cupric compounds. Its univalency in the cuprous compounds accords with the position of the metal in the periodic system, and is exemplified by the resemblance of the cuprous halides to the halides of silver and univalent gold, and also by the isomorphism of cuprous sulphide and silver sulphide. The bivalency of the atom in the cupric compounds is in agreement with the properties of many of its derivatives, a typical example being the isomorphism of cupric sulphate with the sulphates of ferrous iron, zinc, magnesium, and manganese. 

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