Beryllium salts, hydrolysis

NHj and CO2 and precipitates a high-purity, basic beryllium carbonate. If the aqueous system has the stoichiometry of (NtL Be COi) , analogous to the ammonium nranyl carbonate system, the basic beryllium carbonate product of hydrolysis is 2BeCC>3 Be(OH)2- This compound is readily dissolved in all mineral acids, making it a valuable starting material for laboratory synthesis of beryllium salts of high purity. 

Beryllium hydroxide, [CAS 13327-32-7], Be(OH)2 is precipitated as an amorphous, gelatinous material by addition of ammonia or alkali to a solution of a beryllium salt at slightly basic pH values. A pure hydroxide can be prepared by pressure hydrolysis of a sluriy of beryllium basic carbonate in water at 165°C. All forms of beryllium hydroxide begin to decompose in air or water to beryllium oxide at 190c C. 

The addition of soluble carbonates to beryllium salt solutions gives only basic carbonates. Beryllium salt solutions also have the property of dissolving additional amounts of the oxide or hydroxide. This behavior is attributable to the formation of complex species with Be—OH—Be or Be—O—Be bridges. The rapidly established equilibria involved in the hydrolysis of the [Be(H20)4]2+ ion are very complicated and depend on the anion, the concentration, the temperature, and the pH. The main species, which will achieve four-coordination by additional water molecules, are considered to be Be2(OH)3+ and Be3(OH)3+ (probably cyclic). 

PROBABLE FATE photolysis no data found on photolysis of beryllium oxidation not an important process hydrolysis soluble beryllium salts are hydrolyzed to form insoluble beryllium hydroxides volatilization airborne dusts are the most widely known hazard associated with beryllium sorption no data found on adsorption of beryllium biological processes only slightly bioaccumulated... 

Gives figures for the hydrolysis of solutions of BeClj, Be(N03)2, and BeSO, compared with corresponding salts of iron and aluminum. The beryllium salts showed smaller degree of hydrolysis than either of the other.s,... 

Chemically, the basic beryllium compounds are stable toward heat, toward oxidation except under very drastic conditions (e.g., boiling with nitric acid), and toward cold water. Treatment with boiling water usually effects hydrolysis slowiy treatment with mineral acids normally yields the corresponding beryllium salt and the free organic acid. 

Many well ddined and crystalline double salts of beryllium have been made In many cases the double salts are readily prepared and are quite stable when the normal single salt can not be produced at all or only in the absence of water. This is notably true in the case of the double carbonates, chlorides, iodides, nitrites and sulphites. In general these salts have been but little studied, their discoverers- being content with their identification and analysis. Being less subject to the confusing action of hydrolysis than either the normal or basic salts of beryllium, their description and identity can, as a rule, be depended upon when found in literature. 

Morin, the coloring matter of fustic, is 3,5,7,2, 4 -pentahydroxy flavone (I). Its alcohol solutions react with aluminum salts in neutral or acetic acid solution to give an intense green fluorescence in daylight and ultraviolet light. The fluorescence is due to the formation of a colloidally dispersed inner complex aluminum salt of morin with the probable structure (II), or to an adsorption compound of morin with alumina. Beryllium, indium, gallium, thorium and scandium salts also form fluorescent compounds with morin. The pH of the system has much influence in these reactions. The only metal ion whose reaction with morin is independent of pH is Zr+ or its hydrolysis product (compare page 519). 

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