Silver ammonia complex oxide

The silver chloride (AgCl) is dissolved as the stable silver-ammonia-complex ion [Ag(NH3) 2+] is formed. Meanwhile, the mercury II chloride (HgCl2) is undergoing oxidation and reduction at the same time Mercury metal (Hg) and mercury II amidochloride (HgNH2Cl) are formed and appear, respectively, black and gray in color ... 

Both the ions of Ag+ and Cif are easily complexed by ammonia (amine) and the corresponding complexes are very stable [204]. In the system of silver-ammonia complex ions the oxidation-reduction standard electrode potential of silver is expressed by... 

Silver ion, Ag, oxidizes aldehydes selectively in a convenient functional-group test for aldehydes. The Tollens test involves adding a solution of silver-ammonia complex (the Tollens reagent) to the unknown compound. If an aldehyde is present, its oxidation reduces silver ion to metallic silver in the form of a black suspension or a silver mirror deposited on the inside of the container. Simple hydrocarbons, ethers, ketones, and even alcohols do not react with the Tollens reagent. 

A test for aldehydes. The Tollens reagent is a silver-ammonia complex Ag(NH3)2 OH]. Tollens reagent oxidizes an aldehyde to a carboxylate salt and deposits a silver mirror on the inside of a glass container, (p. 862)... 

Ores of silver native silver, argentite, cerargyrite (horn silver). Metallurgy of silver cyanide process, amalgamation process, Parkes process. O mpoimds of silver silver oxide, silver chloride, silver bromide, silver iodide, silver ammonia complex, silver cyanide complex, silver thiosulfate complex, silver nitrate. 

Tollen s test. Glucose and other aldoses are oxidized by an aqueous solution of a silver-ammonia complex. What are the reaction products ... 

Aldehydes are also oxidized to carboxylic acids by silver ion. One common laboratory procedure uses Tollens reagent, prepared by dissolving AgN03 in water, adding sodium hydroxide to precipitate silver ion as AggO, and then adding aqueous ammonia to redissolve silver ion as the silver-ammonia complex ion ... 

A laboratory test that distinguishes aldehydes from ketones takes advantage of their different ease of oxidation. In the Tollens silver mirror test, the silver-ammonia complex ion is reduced by aldehydes (but not by ketones) to metallic silver. The equation for the reaction may be written as follows ... 

Setting Up In a 10-mL Erlenmeyer flask, prepare a solution of silver ammonia complex from 2.5 mL of 0.1 A/f silver nitrate solution by adding ammonium hydroxide solution dropwise. Brown silver oxide forms first add just enough ammonium hydroxide to dissolve the silver oxide. Dilute the solution by adding 1.5 mL of water. 

Another method for distinguishing between aldehydes and ketones is Tollens s test. A positive test indicates the presence of an aldehyde function, whereas no reaction occurs with ketones. Tollens s reagent consists of silver-ammonia complex, Ag(NH3)2, in an ammonia solution. This reagent oxidizes both aliphatic and aromatic aldehydes to the corresponding carboxylic acids silver ion is reduced to elemental silver, which is deposited as a silver mirror on the glass wall of a clean test tube. Thus, the formation of the silver mirror or of a precipitate is considered a positive test. Equation 25.12 shows the reaction that occurs. 

Tollens reagent is a basic solution of a silver ammonia complex ion. When an aldehyde is added to a test tube containing Tollens reagent, the aldehyde is oxidized and deposits metallic silver as a mirror on the wall of the test tube. 

To minimize the formation of fuhninating silver, these complexes should not be prepared from strongly basic suspensions of silver oxide. Highly explosive fuhninating silver, beheved to consist of either silver nitride or silver imide, may detonate spontaneously when silver oxide is heated with ammonia or when alkaline solutions of a silver—amine complex are stored. Addition of appropriate amounts of HCl to a solution of fuhninating silver renders it harmless. Stable silver complexes are also formed from many ahphatic and aromatic amines, eg, ethylamine, aniline, and pyridine. 

Oxidation of the complexes [Ag(Py)4][MoF6] and [Ag(Py)2][UF6] in acetonitrile by MoF6 and UF6, respectively, leads to the silver(III) compounds [Ag(Py)4(NCMe)][MoF6]3 and [Ag(Py)2(NC-Me)3][UF6]3, which are strong oxidizing agents.167 Other pyridine silver(III) complexes have been obtained by oxidation of silver nitrate and ammonia with ammonium peroxydisulfate in aqueous... 

A mixed-valence silver(I)-silver(III) cryptate complex has been synthesized by condensation of tris(3-aminopropyl)amme and terephthaldehyde in the presence of AgNOs. Other pyridine silver(III) complexes have been obtained by oxidation of silver nitrate and ammonia with ammonimn peroxydisulfate in aqueous ammonia solution. An air-stable diamagnetic silver(III) complex of a N-confused tetraphenylporphyrin, 5,10,15,20-tetraphenyl-2-aza-21-carboporphyrin argentate(III), has been described. ... 

Similar observations on the oxidation of the thallium atom or on the reduction of T1+ have been made by pulse radiolysis. They are in agreement, as for silver, with the value determined from the electrode potential and the sublimation energy of the bulk metal into atoms, i.e. °(T1 /T1 ) = —1.9 Vnhe-Silver ions complexed by cyanide, ammonia, or EDTA, Ag L, are not reduced by the radical (CH3)2C OH, even under basic conditions, and the redox potential of these complexed forms must be more negative than —2.1 According... 

Softer Lewis bases have to be applied in etch baths for oxides and salts of metals or semiconductors with a softer Lewis acid character of their cations. Materials consisting of compounds of heavier metals frequently become dissolvable in the presence of higher halogenide imis like chloride or bromide. So, Cu(l) which is not well solvated in water as the unbound ion becomes dissoluble in the presence of, for example, chloride ions by forming Cu(l) chlorocomplexes. The choice of suitable complex ligands depends on the particular coordination chemistry of the heavier metals or semiconductors inside the oxidic or saltlike functional materials. In some cases, ammonia or amines are suitable. So, the formatiOTi of a silver diamine complex can be used for the etching of Ag(l) compounds,... 

The high adsorption capacity of Ag+ ions by all the activated carbons was attributed to the reduction of Ag+ ions to metallic silver by the hydroquinone groups present on the carbon surface, which in turn are oxidized to quinone groups. This redox process is supported by the standard reduction potentials of Ag+ (Ag+ + e Ag, E = 0.7996 V) and quinhydrone electrode, = 0.6995 V. The increase in adsorption of Ag+ ions by the ammonia-treated sample was attributed to the formation of silver amino complexes which are quite stable under the conditions used in these studies. 

Ag(in)(H3l06)(H20)2] is the reactive silver(III) species involved in the diper-iodatoargentate(in) oxidation of nitrilotriacetic acid (NTA) in a mildly basic medium to produce formaldehyde and ammonia. NTA binds to the silver(III) complex in an axial fashion and two electrons are transferred from bound NTA to the silver(III) centre sequentially. The latter stages of the reaction consist of a composite process involving the oxidation of NTA and its products in parallel reactions. ... 

The oxide is soluble in ammonia to give the complex [AglNHjlj] (linear). On heating, silver(I) oxide loses oxygen to give the metal (all the coinage metal oxides have low thermal stability and this falls in the order Cu > Ag > Au). 

Isatin (190) is a compound with interesting chemistry. It can be iV-acetylated with acetic anhydride, iV-methylated via its sodium or potassium salt and O-methylated via its silver salt. Oxidation of isatins with hydrogen peroxide in methanolic sodium methoxide yields methyl anthranilates (81AG(E)882>. In moist air, O-methylisatin (191) forms methylisatoid (192). Isatin forms normal carbonyl derivatives (193) with ketonic reagents such as hydroxylamine and phenylhydrazine and the reactive 3-carbonyl group also undergoes aldol condensation with active methylene compounds. Isatin forms a complex derivative, isamic acid (194), with ammonia (76JCS(P1)2004). 

Catalytic forms of copper, mercury and silver acetylides, supported on alumina, carbon or silica and used for polymerisation of alkanes, are relatively stable [3], In contact with acetylene, silver and mercury salts will also give explosive acetylides, the mercury derivatives being complex [4], Many of the metal acetylides react violently with oxidants. Impact sensitivities of the dry copper derivatives of acetylene, buten-3-yne and l,3-hexadien-5-yne were determined as 2.4, 2.4 and 4.0 kg m, respectively. The copper derivative of a polyacetylene mixture generated by low-temperature polymerisation of acetylene detonated under 1.2 kg m impact. Sensitivities were much lower for the moist compounds [5], Explosive copper and silver derivatives give non-explosive complexes with trimethyl-, tributyl- or triphenyl-phosphine [6], Formation of silver acetylide on silver-containing solders needs higher acetylene and ammonia concentrations than for formation of copper acetylide. Acetylides are always formed on brass and copper or on silver-containing solders in an atmosphere of acetylene derived from calcium carbide (and which contains traces of phosphine). Silver acetylide is a more efficient explosion initiator than copper acetylide [7],... 

Remove the bath with water, remove the rubber tube with a bent glass tip from the end of the apparatus, and pass the carbon(II) oxide through ammonia solutions of silver nitrate and copper(I) chloride poured into test tubes. What happens Does the carbon(II) oxide exhibit the same properties in these reactions How can one prove that carbon(II) oxide will evolve when the formed complex compound of copper(I) is heated ... 

The complex salts of precious metals, formed by the action of ammonia either on aqueous solutions of silver, gold and platinum salts or on silver oxide were the first substances tp reveal the ability to explode violently on heating, on direct contact witl flame or by friction or impact ( fulminating silver and gold). 

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