Determination gallium

The detection limit for gallium determination at 287.4 nm in an air-acetylene flame is only about 70 ng ml - and that by flame AFS is not much better, and sometimes even worse.1 The detection limit by flame AES at 403.3 nm is appreciably better, especially if a nitrous oxide-acetylene flame is used. This reflects the low excitation energy. These values are too low to make the direct determinations useful in environmental applications, and therefore solvent extraction is often used for pre-concentration.1 One method often used is the extraction of the anionic keto-chloro complex from strong hydrochloric acid solution (e.g. 5.5M) into 4-methylpentan-2-one.25,26 Co-extraction of iron may... 

A solution of Li[GaH4] in diethyl ether is prepared by the standard methods,J1 and is stored in a needle-valve O-ring flask. The concentration of Li[GaH4]-ether solution is determined by hydrolysis of a known volume of the solution followed by gallium determination by ethylenediamine-tetraace-tic acid, disodium salt using copper-PAN [l-(2-pyridylazo)-2-naphthol copper complex] as the indicator.4 It is assumed that all the gallium is present as the tetrahydrogallate. Only an approximate concentration need be determined since an excess of sodium hydride or potassium hydride is used. 

Tin can be tolerated up to 50 fold excess. Thus, for practical purposes of coal or fly ash analysis, no particular interference is expected in the gallium determination. 

Galactonurate, determination of 60-65 Gallium, determination of 157 Gas chromatography, applications of... 

The actual structure at a vapor-liquid interface can be probed with x-rays. Rice and co-workers [72,73,117] use x-ray reflection to determine the composition perpendicular to the surface and grazing incidence x-ray diffraction to study the transverse structure of an interface. In a study of bismuth gallium mixtures. 

Gainum (I)—Gallium (HI) Compounds having the formula Ga2X where X = Cl, Bt, or I, ate known. The stmcture of these mixed valance compounds, Ga" (GaX4) , has been better understood in recent years (26,27). Some properties ate Hsted in Table 5. Other compounds such as Ga" (Ga2X2) , where X = Cl or Bt, have also been identified and the stmctures determined (28,29). 

Fluorimetry is generally used if there is no colorimetric method sufficiently sensitive or selective for the substance to be determined. In inorganic analysis the most frequent applications are for the determination of metal ions as fluorescent organic complexes. Many of the complexes of oxine fluoresce strongly aluminium, zinc, magnesium, and gallium are sometimes determined at low concentrations by this method. Aluminium forms fluorescent complexes with the dyestuff eriochrome blue black RC (pontachrome blue black R), whilst beryllium forms a fluorescent complex with quinizarin. 

For liquid electrode metals (mercury, gallium) the determination of the surface tension can be applied. From changes of the surface tension as a function of dissolved adsorbable species the surface coverage... 

C09-0025. Describe the geometry and draw a ball-and-stick sketch of gallium triiodide. C09-0026. Describe the geometry and draw a ball-and-stick sketch of the ASCI4 anion. C09-0027. Determine the Lewis structure and describe the geometry of XeOF4. ... 

Crystals of complex 112 suitable for an X-ray structure determination were obtained on cooling a solution in pentane to — 30 °C. The structure determined is shown in Fig. 7.9. The most remarkable structural feature of 112 is that the gallium center is connected to the zirconium through two different c-carboxylic bridges. One of them contains the cyclo-C6Hg system, which is t]1-bonded to gallium and r 2-coordinated to zirconium. It is noteworthy that carbon atom C-2 is planar tetracoordinate. It is connected to four neighboring atoms in the c-plane, specifically to carbon atoms C-l and C-3 and to both metal centers [175]. 

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