Aluminium and its compounds

The action of aluminium and its compounds is not fully understood. Pyridine probably acts by the intermediate formation of the perbromide, as explained. 

The dithizone method has been used for determining silver in sewage [12], aluminium and its compounds [51], uranium compounds [52], tin [26], lead [53], gold [54], metal tellurides [55,56], and glass and ceramic materials [57]. 

A rare element occurring in the emerald and beryl. The metal resembles aluminium and its compounds resemble those of Al,... 

Aluminium is the third most abundant element in the earth s crust and is used widely in the manufacture of construction materials, wiring, packaging materials and cookware. The metal and its compounds are used in the paper, glass and textile industries as well as in food additives. Despite the abundance of the metal, its chemical nature effectively excludes it from normal metabolic processes. This is due largely to the low solubility of aluminium silicates, phosphates and oxides that result in the aluminium being chemically unavailable. However, it can cause toxic effects when there are raised concentrations of aluminium in water used for renal dialysis. These effects are not seen when aluminium is at the concentrations usually present in drinking water. There is currently much activity to examine the factors that influence uptake of aluminium from the diet. 

Beryllium ion (Be2+) is very small having high polarising power. It forms compound with more covalent character and its compounds show similarity with those of aluminium and with group 12 element Zn. 

Cd and its compounds find applications in several industrial materials electrode materials in Ni-Cd batteries (about 70% of total produced Cd), pigments in ceramics, glasses, paper, plastics, artists colors (13%), stabilizers for polyvinyl chloride and related polymers (7%), coatings on steel, aluminium, and other nonferrous metals (8%), and specialized alloys (see Alloys) and others (2%). 

Determinations of aluminium with the use of various triphenylmethane reagents were carried out in natural waters [47,108], soil extracts [44,109], silicate rocks [46,50], minerals [49], titanium and its compounds [5,48], copper alloys [45], glass and slags [110]. 

Beryllium (Be, at. mass 9.012) forms cations Be ". In its chemical properties, beryllium resembles magnesium and aluminium. Beryllium hydroxide is precipitated at pH 6, and dissolves in alkali hydroxides. Freshly precipitated Be(OH)2 dissolves in NaaCOs solution to form a rather unstable carbonate complex. Beryllium also forms weak complexes with citrate, tartrate, and fluoride anions. Beryllium and its compounds are highly toxic. 

The dithizone method has been applied in the determination of zinc in sewage [89], cadmium and its compounds [31], aluminium [90,91], nickel [11], cobalt [12], gold [92], germanium compounds [37], and tellurium [93]. Zinc was determined with dithizone in aqueous media in the presence of dodecyl sulphate using the FIA technique [94]. 

It is possible to draw conclusions about the atomization mechanism from the thermal pretreatment/atomization curves, when melting point, boiling point, and decomposition point for the analyte and its compounds are entered on these plots. Figure 66 shows the thermal pretreatment/atomization curves for cadmium and aluminium. The initial pre-atomization losses and the appearance temperature are below the melting point of cadmium. This... 

On Aluminium and Gallium Compounds. It was mentioned that PH3 is irreversibly adsorbed on alumina gels. However, no details were given [1]. An adsorption isotherm for PH3 adsorption (p< 35 Torr) on AI2O3 at 20 C is displayed in [2,3]. The percentage of PH3 (500 pg in Ng) sorbed on AI2O3 between 50 and 120"C is given in [4]. 

However, as Boisbaudran went on studying the properties of metallic gallium and its compounds, his results continued to coincide with Mendeleev s predictions. For instance, in May 1876, the French scientist established that gallium was readily fusible (its melting point is29.5 C), its appearance remained the same after storage in air, and it was slightly oxidized when heated to redness. The same properties of eka-aluminium were predicted by Mendeleev in 1870, who cal-... 

LiAlH4, lithium tetrahydridoaluminate ("lithium aluminium hydride . so-called) is an excellent reducing agent in ether solution for both organic and inorganic compounds it may be used to prepare covalent hydrides SiH ether, for example... 

Aluminium is not found free but its compounds are so widespread that it is the most abundant metal in the earth s crust. Aluminosilicates such as clay, kaolin (or china clay), mica and feldspar are well known and widely distributed. The oxide. AI2O3. occurs (anhydrous) as corundum and emery, and (hydrated) as bauxite. Cryolite. Na,AlF. (sodium hexafluoroaluminate). is found extensively in Greenland. 

Scandium is not an uncommon element, but is difficult to extract. The only oxidation state in its compounds is -I- 3, where it has formally lost the 3d 4s electrons, and it shows virtually no transition characteristics. In fact, its chemistry is very similar to that of aluminium (for example hydrous oxide SC2O3, amphoteric forms a complex [ScFg] chloride SCCI3 hydrolysed by water). 

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