Indium dissolved

Indium dissolves in mineral acids. Concentration or evaporation of the solution produces corresponding salts. With sulfuric acid, it forms indium trisulfate, In2(S04)s and indium hydrogen sulfate, In(HS04)2. The latter salt is obtained upon concentration of trisulfate solution. With nitric acid, the salt is indium nitrate trihydrate, In(N03)s 3H2O [13770-61-1] which on dehydration yields monohydrate, In(N03)3 H20. 

We have not attempted to carry out any direct electrochemical syntheses in aqueous media, but there are reports in the literature of work carried out some 40 years ago on the electrochemical oxidation of a number of metals in liquid ammonia [72,73], and since two of the metals in question were gallium and indium, this seemed a natural area for further investigation. The immediate conclusion, which we established by measuring Ep, is that indium is oxidized in liquid ammonia solutions of ammonium halides at -35 °C to the -I-II state, but unfortunately we were not able to isolate any compounds of this oxidation state from the resultant solution, though in one particular case we were able to show by Raman spectroscopy that species with the characteristic j (In-In) stretching mode were present in the solution [74]. When we attempted to work up these solutions both indium and I) halide derivatives of ammonia were obtained, and a mass balance, taking into account the quantity of material isolated and the quantity of indium dissolved, showed that the typical disproportionation reactions of indium +11 were indeed being reproduced under these conditions. We concluded that the overall stoichiometry is... 

Oxonium. Indium dissolves in H3O. The black monoxide, InO, is slowly soluble in acids, but light yellow Iu203 is readily soluble. 

Sulfates. Indium metal and its oxides dissolve in warm sulfuric acid to give a solution of the trisulfate [13464-82-9], In2(S0 2- It is a white, crystalline, deUquescent soHd, readily soluble in water that forms double salts with alkaLi sulfates and some organic substituted ammonium bases. Concentration of the acidified trisulfate solution produces indium acid sulfate crystal [57344-73-7], In(HS0 2> other reaction conditions give basic sulfates. 

Sulfides. The main sulfide of indium is I1I2S2 [12030-24-9], which can be prepared by heating the metal with sulfur or by precipitation from weak acid solutions of indium salts by H2S. Precipitated I1I2S2 varies in color from yellow to red-brown, and in crystal size depending on formation conditions. It dissolves in acids and sodium sulfide solution. Other reported sulfides of indium ate InS [12030-14-7], a red-brown soHd In2S [12196-52-0], and In S [12142-00-5]. 

Modifications to Precipitates. Silicon is sometimes added to Al—Cu—Mg alloys to help nucleate S precipitates without the need for cold work prior to the elevated temperature aging treatments. Additions of elements such as tin [7440-31-5] Sn, cadmium [7440-43-9] Cd, and indium [7440-74-6] In, to Al—Cu alloys serve a similar purpose for 9 precipitates. Copper is often added to Al—Mg—Si alloys in the range of about 0.25% to 1.0% Cu to modify the metastable precursor to Mg2Si. The copper additions provide a substantial strength increase. When the copper addition is high, the quaternary Al CuMg Si Q-phase must be considered and dissolved during solution heat treatment. 

Spray Pyrolysis. In spray pyrolysis, a chemical solution is sprayed on a hot surface where it is pyrolyzed (decomposed) to give thin films of either elements or, more commonly, compounds (22). Eor example, to deposit CdS, a solution of CdCl plus NH2CSNH2 (thiourea) is sprayed on a hot surface. To deposit Iu202, InCl is dissolved in a solvent and sprayed on a hot surface in air. Materials that can be deposited by spray pyrolysis include electrically conductive tin—oxide and indium/tin oxide (ITO), CdS, Cu—InSe2, and CdSe. Spray pyrolysis is an inexpensive deposition process and can be used on large-area substrates. 

Indium (III) oxide [1312-43-2] M 277.6, d 7.18, m sublimes at 850°. Wash with H2O and dry below 850°. Volatilises at 850° and dissolves in hot mineral acids to form salts. Store away from light because it darkens due to formation of In. 

Indium (III) sulfate (5H2O) [17069-79-3] M 607.9, d 3.44. Dissolve in strong H2SO4 and slowly evaporate at ca 50°. Wash crystals with glacial AcOH and then heat in a furnace at a temperature of 450-500° for 6h. Sol in H2O is 5%. The pentahydrate is converted to an anhydrous hygroscopic powder on heating at 500° for 6h but heating above this temperature over N2 yields the oxide sulfate. Evaporation of neutral aqueous solutions provides basic sulfates. [J Am Chem Soc 55 1943 1933, 58 2126 1936.]... 

FIG. 26 Cyclic voltammograms of 40 monolayers of Langmuir-Schaefer films of cytochrome P450SCC on indium-tin oxide glass plate (ITO) in 10 mM phosphate buffer at a scan rate of 20 mV/s between 0.4 and —0.4 V vs. Ag/AgCl. LS films on ITO worked as the working electrode, platinum as the counter, and Ag/AgCl as the reference electrode. Cholesterol dissolved in X-triton 100 was added 50 p.1 at a time (1) with cholesterol, (2) 50 p.1 of cholesterol, (3) 100 p.1 cholesterol, and (4) 150 p.1 of cholesterol. 

A liquid metal alloy [36] containing gallium, indium, and tin has been proposed as an additive to Portland cement. A formulation is shown in Table 18-10. The liquid metal alloy has a melting point of 11° C. Its presence does not cause corrosion of stainless steel up to 250° C but causes corrosion of steel alloys at temperature above 35° C, and it dissolves aluminum at room temperature. The alloy is harmless to skin and mucous membranes. 

Berndt et al. [740] have shown that traces of bismuth, cadmium, copper, cobalt, indium, nickel, lead, thallium, and zinc could be separated from samples of seawater, mineral water, and drinking water by complexation with the ammonium salt of pyrrolidine- 1-dithiocarboxylic acid, followed by filtration through a filter covered with a layer of active carbon. Sample volumes could range from 100 ml to 10 litres. The elements were dissolved in nitric acid and then determined by atomic absorption or inductively coupled plasma optical emission spectrometry. 

Since CuInTe2 does not significantly dissolve in hydrazine, a new stepwise process was devised for dissolution, which involves separate indium- and... 

Al, Ga, In and T1 differ sharply from boron. They have greater chemical reactivity at lower temperatures, well-defined cationic chemistry in aqueous solutions they do not form numerous volatile hydrides and cluster compounds as boron. Aluminium readily oxidizes in air, but bulk samples of the metal form a coherent protective oxide film preventing appreciable reaction aluminium dissolves in dilute mineral acids, but it is passivated by concentrated HN03. It reacts with aqueous NaOH, while gallium, indium and thallium dissolve in most acids. 

Indium also has many of the characteristics that make Al and Ga very useful for such applications. Particularly important is its capacity to dissolve Si, Ge and several lanthanide and transition metals, producing highly reactive forms of the elements. Moreover In does not form binaries with Si and Ge and has a low-melting point. RNiGe2 compounds, for instance, were prepared from stoichiometric quantities of the components in fine powder mixed with a 10 fold quantity of In in alumina tubes. These, flame sealed in fused silica tubes, were slowly heated to 1000°C, held at this temperature for a few hours, ramped down to 850°C, held for an additional 4 days and finally cooled down to room temperature over the course of another 4 days. Compound isolation from the In excess was performed by centrifugation at 300°C through a coarse frit. Further purification was carried out by a 15-minute submersion and sonication in 6 M aqueous HC1 (Salvador et al. 2004). 

SWV was used for the investigation of charge transfer kinetics of dissolved zinc(II) ions [215-218] and uranyl-acetylacetone [219], cadmium(II)-NTA [220] and mthenium(III)-EDTA complexes [221], and the mechanisms of electrode reactions of bismuth(III) [222], europium(III) [223,224] and indium(III) ions [225], 8-oxoguanine [226] and selenium(IV) ions [227,228]. It was also used for the speciation of zinc(II) [229,230], cadmium(II) and lead(II) ions in various matrices [231-235]. 

Indium trioxide dissolves in sulfuric acid, forming indium trisulfate ... 

The oxide dissolves in acetic acid, forming indium triacetate ... 

In another industrial process, flue dusts from smelting lead and zinc concentrates are boiled in acidified water. Thallium dissolves and is separated from insoluble residues by filtration. Dissolved thallium in solution then is precipitated with zinc. Thallium is extracted from the precipitate by treatment with dilute sulfuric acid which dissolves the metal. The solution may also contain zinc, cadmium, lead, copper, indium, and other impurities in trace amounts. These metals are precipitated with hydrogen sulfide. The pure thallium sulfate solution then is electrolyzed to yield thallium. 

The conventional preparative routes to anionic, neutral, or cationic complexes of indium start with the metal, which is dissolved in a suitable mineral acid to give a solution from which hydrated salts can be obtained by evaporation. These hydrates react with a variety of neutral or anionic ligands in nonaqueous solvents, and a wide range of indium(III) complexes have been prepared in this manner.1 Alternatively, the direct high-temperature oxidation of the metal by halogens yields the anhydrous trihalides, which are again convenient starting materials in synthetic work. In the former case, the initial oxidation of the metal is followed by isolation, solution reaction, precipitation, and recrystallization. 

Indium metal (0.85 g) is maintained at +15 V in a solution phase of 100 mLof 50 50 benzene-dimethyl sulfoxide (dmso). Benzene is purified as in Section A above dimethyl sulfoxide is dried over 4A molecular sieves before use. The cell is cooled in an ice bath throughout the experiment. Chlorine gas is bubbled slowly through the solution phase (about one bubble per second from a 2-mm tube) for 2 hours. At the end of this period, the solution is brown, and most of the indium has dissolved approximately 0.1 g of corroded material remains. 

A transparent electrode substrate was prepared by coating indium tin oxide (ITO) on a glass substrate and washing the substrate. ITO was then patterned using a photoresist resin and an etchant to specified patterns and the substrate washed. A hole injection layer was formed by coating a selected experimental agent dissolved in toluene to a thickness of about 50 nm and baking at 110°C for 1 hour. 

Chemistry. The indium metal was melted (mp 156°C) into a flask where it was dissolved in hot 6 M HC1. Since the target material was known to contain Sb impurity, filtration was required at this point in the procedure. After filtration the solution was adjusted to 3 M HC1 by the addition of a suitable volume of distilled water. Table I is a list of the elements that must be separated to obtain pure Cd-109. This solution was applied to an AG-1X8 anion column, 200 to 400 mesh (8). The column was 1.2 cm in diameter with a total bed volume dependent on the quantity of target used. Bed volumes of 20 ml and 40 ml were successfully used. 

F. C. Mathers and C. G. Schluderberg 124 prepared indium iodate, In(I03)3, by mixing soln. of indium trichloride and potassium iodate. The precipitate is amorphous. The mixture was evaporated to dryness on a water-bath the residue extracted on a Gooch s crucible with warm water and dried in vacuo over sulphuric acid. The mass was dissolved in boiling nitric acid (1 10), and on evaporation white crystals of indium iodate were formed. 100 grms. of water at 20° dissolve 0 067 grm., and 100 grms. of nitric acid (1 5) at 80° dissolve 0 67 grm. of the salt. It also dissolves in dil. sulphuric or hydrochloric acid. The soln. in the last-named add decomposes with the liberation of chlorine. The crystals decompose with the evolution of iodine when heated by a free flame and explode if touched with a red-hot iron wire. 

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