Group 2 metal chlorides solutions

Other Metals. Ruthenium, the least expensive of the platinum group, is the second best electrical conductor, has the hardest deposit, and has a high melting point. A general purpose bath uses 5.3 g/L of mthenium as the sulfamate salt with 8 g/L sulfamic acid, and is operated at 25—60°C with a pH of 1—2. Osmium has been plated from acid chloride solutions (130) and iridium from bromide solutions, but there are no known appHcations for these baths. 

Copper forms practically aU its stable compounds in -i-l and +2 valence states. The metal oxidizes readily to -i-l state in the presence of various com-plexing or precipitating reactants. However, in aqueous solutions +2 state is more stable than -i-l. Only in the presence of ammonia, cyanide ion, chloride ion, or some other complexing group in aqueous solution, is the +1 valence state (cuprous form) more stable then the +2 (cupric form). Water-soluble copper compounds are, therefore, mostly cupric unless complexing ions or molecules are present in the system. The conversion of cuprous to cupric state and metalhc copper in aqueous media (ionic reaction, 2Cu+ — Cu° -i- Cu2+) has a Kvalue of 1.2x106 at 25°C. 

Quickert, S. C. and Bernhard, R. A. 1982. Recovery of lactose from aqueous solution using Group IIA metal chlorides and sodium hydroxide. J. Food Sci. 47, 1705-1709. 

The use of amine salts in the commercial solvent extraction of the platinum-group metals from chloride solutions is described in Section 63.3.2.5. 

The use of solvating extractants in the recovery of gold and platinum-group metals (PGM) was described in the previous section. These extractants have also found some specialized applications in the extractive metallurgy of base metals. For example, they have been used in the recovery of uranium, the separation of zirconium and hafnium, the separation of niobium and tantalum, the removal of iron from solutions of cobalt and nickel chlorides, and in the separation of the rare-earth metals from one another. 

The GC determination of metal halides is complicated by the instability in chromatographic systems and different analytical solutions. Fluorides and chlorides are the halides that are used most often for different groups of metals the former are more volatile, but they also tend to be more reactive. The GC analysis of metal chlorides and fluorides necessitates highly inert column packings and inert chromatographic accessories, particularly the injection port, material of the column and the detector. Conversion of metal ions into halides involves different halogenation techniques. Direct reactions of metals... 

Group V. Na, K, and Li The metals are present as chlorides in neutral solution. The solvent used is methanol. The position of the alkali metal chloride bands is detected by spraying with 01m silver nitrate and saturated fluorescein in 50 per cent alcohol, and then drying the strip. The RF values are Li, 0 8 Na, 0-5 K, 0-1 (see Fig. VI.5[Pg.503]

Molybdenum and tungsten are rendered passive more readily in acid than in alkaline solution this is the reverse of the behavior exhibited by chromium and the iron-group metals. Although oxidizing agents generally favor passivity, such is not the case with a tin anode in this instance, too, chloride ions do not have the inhibiting effect they have in other cases. It is apparent, therefore, that each metal requires its own specific conditions in order that it may be rendered passive. 

These observations, together with the results of solution conductivity measurements, can be explained if six groups, either chloride ions or ammonia molecules, remain bonded to the cobalt ion during the reaction and the compounds are formulated as shown in Table 1.4, where the atoms within the square brackets form a single entity which does not dissociate under the reaction conditions. Werner proposed the term secondary valence for the number of groups bound directly to the metal ion in these examples the secondary valences are six in each case. 

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