Of silver metal

Elemental sulfur in either its ore or its refined state can generaUy be recognized by its characteristic yeUow color or by the generation of sulfur dioxide when it is burned in air. Its presence in an elemental state or in a compound can be detected by heating the material with sodium carbonate and mbbing the fused product on a wet piece of silver metal. A black discoloration of the silver indicates the presence of sulfur. The test is quite sensitive. Several other methods for detecting smaU amounts of elemental sulfur have also been developed (34). 

The darkening reaction involves the formation of silver metal within the silver haUde particles containing traces of cuprous haUde. With the formation of metallic silver, cuprous ions are oxidized to cupric ions (1,4). The thermal or photochemical (optical bleaching) reversion to the colorless or bleached state corresponds to the reoxidation of silver to silver ion and the reduction of cupric ion to reform cuprous ion. 

Thin films of photochromic silver complex oxides were prepared by anodic oxidation of silver metal films (15). Complex oxides, such as Ag2V04, Ag SiO, and Ag2P04, darkened by exposure to visible light, but required heating to 150—250°C for thermal bleaching. 

How many grams of silver metal will react with 2.0 liters of 6.0 M HNO3 The reaction is... 

FIGURE K.6 (a) A silver nitrate solution is colorless, (b) Some time after the insertion of a copper wire, the solution shows the blue color of the < opper(ll) ion and the formation of crystals of silver metal on the surface ol the wire. 

A total charge of 96.5 kC is passed through an electrolytic cell. Determine the quantity of substance produced in each case (a) the mass (in grams) of silver metal from a silver nitrate solution (b) the volume (in liters at 273 K and... 

Most pure transition metals have the shiny gray appearance that is termed silvery because of the appearance of silver metal. However, some transition metals have other colors—for example, the orange color of copper and the yellow hue of gold. 

Ag(I) and Cu(II) are readily used in neutral solution, although oxidations by Ag(I) are often affected by the deposition of silver metal. Theoretically Cu(II) can behave either as a two- or a one-equivalent reagent, but it usually functions as the latter. The tendency of Cu(I) to disproportionate is normally suppressed by working with solvents such as pyridine which form stable complexes with this oxidation state. 

Mogi, 1., Okubo, S. and Nakagawa, Y. (1995) Dense radial growth of silver metal leavesin a high magnetic field. J. Phys. Soc. Jpn., 60, 3200-3202. 

EXAMPLE 14.2. How many grams of silver metal can be produced from AgNO, by the passage of 4010C of... 

McLeod, M.C., McHenry, R.S., Beckman, E.J. and Roberts, C.B. (2003) Synthesis and stabilization of silver metallic nanopartides and premetallic intermediates in perfluoropolyether/C02 reverse micelle systems. Journal of Physical Chemistry B, 107 (12), 2693-2700. 

Vest, R. 1986. Ink jet printing of silver metallization for photovoltaics. NASA Center for AeroSpace Information, Pasadena, CA. (Document ID. 19860067973). 

Curtis, C. J. Rivkin, T. Miedaner, A. Alleman, J. Perkins, J. Smith, L. Ginley, D. S. 2002. Direct-write printing of silver metallizations on silicon solar cells. Mater. Res. Soc. Symp. Proc. 730 79-84. 

Worked Example 7.19 We immerse a piece of silver metal into a solution of silver ions at unit activity and at s.t.p. The potential across the cell is 0.799 V when the SHE is the negative pole. What is the standard electrode potential E of the Ag+, Ag couple ... 

A simple and economical method for recovering silver residues by dissolution in used photographic fixer (thiosulfate) solution, then precipitation by addition of zinc powder, is detailed [1]. After the acid digestion phase of silver recovery operations, addition of ammonia followed immediately by addition of ascorbic acid as reducant gives a near-quantitative recovery of silver metal, and avoids the possibility of formation of silver nitride [2],... 

Using Resources Use resources such as the CRC Handbook of Chemistry and Physics, the Merck Index, or the Internet to determine the colors of silver metal and copper nitrate in water. Compare this information with your observations of the reactants and products in step 6. 

The oxidation of an aldose or ketose by silver ions results in the reduction of the silver ion to silver metal. The silver is normally present as Ag (NH3)20H . A positive test has a coating of silver metal precipitating on the sides of the container as a mirror. 

Some other uses of silver metal include its applications as electrodes, catalysts, mirrors, and dental amalgam. Silver is used as a catalyst in oxidation-reductions involving conversions of alcohol to aldehydes, ethylene to ethylene oxide, and ethylene glycol to glyoxal. 

The nuclear density is 1.18 x 1Q14 times that of silver metal. 

Figure 13. Proposed mechanism for activation of silver metal powder for ethylene epoxidation.

Calculate the resultant temperature when 50.0 g of silver metal at 150.0°C is mixed with 50.0 g of water at 20.0°C. (Assume no heat loss to container or surroundings.)... 

The simplest species containing silver(IH) is Ag(OH)4, which in 1.2MNaOH at 25 °C was stable for about 2 hours. The yellow solution gave a single broad absorption band in the UV region with Amax = 270 mm. Preparation of the ion generally involved anodic oxidation of silver metal in basic media.572,573... 

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