Beryllium chemical

Beryllium Oxide. Beryllium oxide [1304-56-9], BeO, is the most important high purity commercial beryllium chemical. In the primary industrial process, beryllium hydroxide extracted from ore is dissolved in sulfuric acid. The solution is filtered to remove insoluble oxide and sulfate impurities. The resulting clear filtrate is concentrated by evaporation and upon cooling high purity beryllium sulfate, BeSO 4H20, crystallizes. This salt is... 

Figure 6. Chart of beryllium chemical shifts. The values recorded are very solvent dependent, even though most of these species may be considered to be entirely covalent. D represents a donor molecule and P a phosphate or...

J. A. Hudbut, The History, Uses, Occurrence, Analytical Chemisty, and Biochemistry of Beryllium, KFP-2132, Dow Chemical U.S.A., Golden, Colo., 1974, pp. 3—9. (Available from National Technical Information Service, TID-4500-R62). 

Diamondlike Carbides. SiUcon and boron carbides form diamondlike carbides beryllium carbide, having a high degree of hardness, can also be iacluded. These materials have electrical resistivity ia the range of semiconductors (qv), and the bonding is largely covalent. Diamond itself may be considered a carbide of carbon because of its chemical stmeture, although its conductivity is low. 

No fewer than 14 pure metals have densities se4.5 Mg (see Table 10.1). Of these, titanium, aluminium and magnesium are in common use as structural materials. Beryllium is difficult to work and is toxic, but it is used in moderate quantities for heat shields and structural members in rockets. Lithium is used as an alloying element in aluminium to lower its density and save weight on airframes. Yttrium has an excellent set of properties and, although scarce, may eventually find applications in the nuclear-powered aircraft project. But the majority are unsuitable for structural use because they are chemically reactive or have low melting points." ... 

Nonferrous metallurgy is as varied as the ores and finished products. Almost every thermal, chemical, and physical process known to engineers is in use. The general classification scheme that follows gives an understanding of the emissions and control systems aluminum (primary and secondary), beryllium, copper (primary and secondary), lead (primary and secondary), mercury, zinc, alloys of nonferrous metals (primary and secondary), and other nonferrous metals. 

Beryllium Compounds - Includes any unique chemical substance that contains beryllium as part of that chemical s infrastructure. 

Chemical Reactivity - Reactivity with Water Reacts vigorously as an exothermic reaction. Forms beryllium oxide and hydrochloric acid solution Reactivity with Common Materials Corrodes most metals in the presence of moisture. Flammable and explosive hydrogen gas may collect in confined spaces Stability During Transport Stable Neutralizing Agents for Acids and Caustics Flush with water and rinse with dilute solution of sodium bicarbonate or soda ash Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Chemical Designations - Synonyms Beryllium Nitrate Trihydrate Chemical Formula Be(N03)j.3H20. 

Chemical Designations - Synonyms Beryllium Sulfate Tetrahydrate Chemical Formula BeS04 4H20. Observable Characteristics - Physical State (as normally shipped) Solid Color White Odor None. Physical and Chemical Properties - Physical State at 15 G and 1 atm. Solid Molecular Weight 177.14 Boiling Point at I atm. Not pertinent (decomposes) Freezing Point Not pertinent Critical Temperature Not pertinent Critical Pressure Not pertinent Specific Gravity 1.71 at 11°C (solid) Vapor (Gas) Density Not pertinent Ratio of Specific Heats of Vapor (Gas) Not pertinent Latera Heat of Vaporization Not pertinent Heat of Combustion Not pertinent Heat of Decomposition Not pertinent. 

The discovery of beryllium in 1798 followed an unusual train of events. The mineralogist R.-J. Haiiy had observed the remarkable similarity in external crystalline structure, hardness and density of a beryl from Limoges and an emerald from Peru, and suggested to L.-N. Vauquelin that he should analyse them to see if they were chemically identical. As a result, Vauquelin showed... 

Electrons are not only charged, they also have a characteristic physicists call spin. Pairing two electrons by spin, which has two possible values, up or down, confers additional stability. Bei yllium (Be, atomic number 4) has two spin-paired electrons in its second shell that are easily given up in chemical reactions. Beryllium shares this characteristic with other elements in column two, the alkaline earth metals. These atoms also generally form ionic bonds. Boron... 

Acetylene works Acrylates works Aldehyde works Aluminum works Amines works Ammonia works Anhydride works Arsenic works Asbestos works Benzene works Beryllium works Bisulfate works Bromine works Cadmium works Carbon disulfide works Carbonyl works Caustic soda works Cement works Ceramic works Chemical fertilizer works Chlorine works Chromium works Copper works Di-isocyanate works Electricity works Fiber works Fluorine works Gas liquor works Gas and coke works Hydrochloric acid works Hydrofluoric acid works Hydrogen cyanide works Incineration works Iron works and steel works... 

Two other factors are noteworthy the deleterious effects on chemical and mechanical properties of small amounts of impurities residual from extraction of the metal, and its toxicity. The first of these factors is obviated by vacuum melting the raw metal (for purification) as an essential prerequisite to further processing. The toxicity of beryllium is essentially a pulmonary problem and great care must be taken in handling the finely divided metal or its compounds. In practice, this type of activity is usually carried out under well-ventilated conditions. Certain tolerance levels for atmospheric beryllium are now internationally accepted and merit careful study before work on beryllium is embarked upon. 

Table 5.1 Chemical composition of various forms of beryllium...

Furthermore, even though a consistent quality of beryllium is now produced, the chemical composition falls far short of the standards found for instance in aluminium generally, the main impurities consist of about 1% of beryllia at grain boundaries, about 0-15% of iron and 0-05-01% of other elements such as silicon, aluminium and carbon. 

Most of the controlled corrosion studies on beryllium have been carried out in the USA in simulated reactor coolants. The latter have usually been water, aerated and de-aerated, containing small amounts of hydrogen peroxide and at temperatures up to 300-350°C. Many variables have been examined, covering surface condition, chemical composition, temperature, pH, galvanic effects and mechanical stress . 

The beryllium atom, like boron and carbon, can promote an electron in order to form more chemical bonds ... 

FIGURE B.12 The location ot the seven elements commonly regarded as metalloids these elements have characteristics of both metals and nonmetals. Other elements, notably beryllium and bismuth, are sometimes included in the classification. Boron (B), although not resembling a metal in appearance, is included because it resembles silicon (Si) chemically. 

The element with Z = 4 is beryllium (Be), with four electrons. The first three electrons form the configuration ls22s1, like lithium. The fourth electron pairs with the 2s-electron, giving the configuration ls22s2, or more simply [He 2s2 (41. A beryllium atom therefore has a heliumlike core surrounded by a valence shell of two paired electrons. Like lithium—and for the same reason—a Be atom can lose only its valence electrons in chemical reactions. Thus, it loses both 2s-electrons to form a Be2+ ion. 

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