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Potassium amalgam

Alloys are metallic substances containing two or more elements which are miscible when molten and do not separate when solidified. They may be liquid or solid. This mixture of elements, usually but not necessarily metals, allows careful manipulation of strength, melting point, corrosion resistance, magnetic, thermal, electrical, and other properties steel, for example, is an alloy of iron and carbon often present with nickel, chromium, copper, aluminium, boron, tungsten, manganese, cobalt, silicon, and other elements. [Pg.151]

Alkali metal alloys and alkaline earth metal alloys have a wide range of applications. The degree to which the alloys retain the pyrophoric or water-reactive properties of their parent metals depends on their concentration in the alloy, the modifying nature of the alloyed components, and the state of subdivision. Many commercial alloys of this type, present no hazard. Others, such as the potassium-sodium alloys used in heat exchangers, present significant concern. Other alkali and alkaline earth metal alloys include [Pg.151]

Amalgams are alloys of mercury with other metals used extensively as chemical reagents and catalysts. The proportion of mercury dictates whether the amalgam is solid or liquid. They include sodium amalgam (Na Rgy), used to manufacture sodium hydroxide, and dental amalgams (alloys of mercury with some combination of silver, copper, tin, gold, or silver) used to fill dental cavities. [Pg.152]

Alkali metal, see Terminology, Metals, p.242 Alkaline earth metal, see Terminology, Metals, p.242 [Pg.152]


Carbon tetrachloride can be reduced to chloroform using a platinum catalyst (10) or zinc and acid. With potassium amalgam and water, carbon tetrachloride can be totally reduced to methane. It is widely employed as an initiator in the dehydrochlorination of chloroethanes at 400—600°C ... [Pg.530]

The Alkali Chlorides as Solutes. In order to make a similar study of the transference of KC1, NaCl, and LiCl between water and methanol-water mixtures, the hydrogen electrode was replaced by an amalgam electrode, as described in Sec. 111. The arrangement when two cells having potassium amalgam electrodes are placed back to back may be written... [Pg.222]

C2F4 reacts with both [HCo(CN)j] and [Co(CN)j] to give, respectively, [HCF2CF2Co(CN)j] -and [(CN)5CoCF2CF2Co(CN)j]"-. The reaction takes place in aqueous solutions at atmospheric pressure 122,121). The presence of potassium amalgam in the former case produces [HCo(CN)5] which gives almost exclusively the HCF2CF2 product. The complexes were isolated by precipitation with ethanol 121). The reaction of [Co"(CN)5] - with CS2 produces [(NC),CoS—C—Co(CN)5] - 125, 5). [Pg.396]

For enzymatic reductions with NAD(P)H-dependent enzymes, the electrochemical regeneration of NAD(P)H always has to be performed by indirect electrochemical methods. Direct electrochemical reduction, which requires high overpotentials, in all cases leads to varying amounts of enzymatically inactive NAD-dimers generated due to the one-electron transfer reaction. One rather complex attempt to circumvent this problem is the combination of the NAD+ reduction by electrogenerated and regenerated potassium amalgam with the electrochemical reoxidation of the enzymatically inactive species, mainly NAD dimers, back to NAD+ [51]. If one-electron... [Pg.107]

In 1825, however, he studied the chemical action of the voltaic current, and tried to isolate chemically the metal believed to be present m alumina. He first prepared liquid aluminum chloride by passing a current of chlorine gas over a mixture of charcoal and alumina heated to redness. By allowing potassium amalgam to react with the aluminum chloride, he prepared an aluminum amalgam, and by distilling off the mercury out of contact with the air, he obtained a metal that looked like tin (11). [Pg.594]

The compound of chlorine with the combustible element of the clay (aluminum chloride) is volatile at a temperature which is not much above that of boiling water, it is somewhat yellowish, perhaps however from admixed carbon it is soft, but still has crystalline form, it absorbs water with avidity and dissolves therein with great ease and with evolution of heat. Rapidly heated with potassium amalgam, it is decomposed, potassium chloride and aluminum amalgam being formed. This amalgam is very quickly decomposed in contact with the atmosphere By distillation without contact with the... [Pg.594]

Oersted s product must have been impure, metallic aluminum containing mercury, but when Wohler repeated the experiment he found that the gray molten mass formed by die action of the potassium amalgam on the aluminum chloride volatilized completely when heated (12, 46). Kirstine Meyer s careful study of Oersted s unpublished notes and I. Fogh s and M. Tosterud and J. D. Edwards repetitions of his experiment show that the great Danish physicist allowed a dilute amalgam containing about 1.5 per cent of potassium to react with excess aluminum chloride, and that it is possible to prepare the metal in this manner (42, 44, 45, 53). [Pg.595]

According to E. Laurent,58 a soln. of sodium nitrate is decomposed in sunlight with the evolution of oxygen, while in darkness it is stable. Zinc dust reduces a soln. of potassium nitrate to the nitrite and hydroxide with the evolution of some oxygen above 60°, only a little nitrite but much nitrogen and ammonia are given off.59 The copper-zinc couple also reduces soln. of the nitrate, first to nitrite, and then to ammonia. Potassium amalgam, stannous chloride, etc., also reduce the nitrates in a similar way. [Pg.820]

Potassium amalgam reduces an aqueous pentathionate solution to tetrathionate and thiosulphate. Metallic copper and silver are blackened by pentathionate solutions. [Pg.220]

The use of lithium amalgam electrodes allows better control of electrode potential than the potassium amalgam electrode. Separations of Sm from Gd, Eu from Sm, Sm from Eu and of Yb from heavy rare earths have been successfully carried out by Onstott [135—137]. [Pg.102]

Although aluminum was predicted by Lavoisier (France) as early as 1782, when he was investigating the properties of aluminum oxide (alumina), the metal was not isolated until 1825 by H.C. Oersted (Denmark). Oersted obtained an impure aluminum metal by heating potassium amalgam with anhydrous aluminum chloride, followed by... [Pg.61]

There are few other examples of complete substitution of carbonyl groups from a homoleptic metal-carbonyl complex by isocyanide ligands [cf. Ni(CO)4 (24), Fe(CO)s (26), and Mo(CO)6 (124)]. The corresponding butyl isocyanide derivative Co CNBuOg was formed by reduction of [Co(CNBu )5]PF6 with potassium amalgam (19). [Pg.222]

Electrolysis of complex salts. The essence of the technique is the following. The mixture of potassium tetraethylaluminate and complex salt of potassium phluoride with triethylaluminum is subjected to electrolysis the anode is lead, the cathode is mercury. Electrolysis dissolves the lead anode, forming tetraethyllead the cathode is covered with potassium amalgam ... [Pg.414]

The obtained sodium tetraethylaluminate is treated with potassium amalgam ... [Pg.414]

The possibility of preparation of sodium or potassium amalgams by an electrochemical process is technically utilized for the production of alkaU hydroxides by decomposition of amalgams with water. [Pg.155]

Particular attention must be paid to the purification of brine when manufacturing potassium hydroxide, as potassium amalgam is much more sensitive to impurities (Mg, Ca, heavy metals) than sodium amalgam. [Pg.295]

Recently it has been found that the cyano complex of Co(II) may be converted (by the action of such powerful reducing agents as potassium amalgam or NaBH4) to the ion HCo(CN)73. The cobalt in this complex... [Pg.398]

Nickel Monocyanide.—Reduction of potassium nickelo-cyanide, K2Ni(CN)4, with potassium amalgam yields a red salt, K2Ni(CN)3, in which nickel appears to be monovalent. Upon acidifying, an orange-yellow precipitate of the monocyanide is obtained, NiCN. It readily oxidises to nickel cyanide, Ni(CN)a.4... [Pg.132]

The salt K2[Os(PF3)4] constitutes the most unequivocal instance in which osmium attains this rare oxidation state (it may always be argued for Os(NO)2(PPh3)2, which has been crystallographically characterized, that — II is only a formal oxidation state). The salt is made from Os(PF3)4H2 and potassium amalgam in ether. It is colourless, and the HNMR and IR spectra are consistent with a symmetrical, presumably tetrahedral, structure.432... [Pg.575]

The potassium salt can be prepared by reducing [Rh2(PF3)8] with potassium amalgam (equation... [Pg.904]

The only other non-carbonyl rhodium(—I) complex that has been isolated is the closely related [Rh(PF2NMe2)4]. The potassium salt can be obtained by reducing [RhCl(PF2NMe2)3] with potassium amalgam.37... [Pg.905]

The yellow dimethylamidophosphine complex is also cleaved by triphenylphosphine and reduced by potassium amalgam.37... [Pg.911]


See other pages where Potassium amalgam is mentioned: [Pg.92]    [Pg.524]    [Pg.216]    [Pg.219]    [Pg.220]    [Pg.222]    [Pg.394]    [Pg.99]    [Pg.246]    [Pg.304]    [Pg.630]    [Pg.209]    [Pg.340]    [Pg.234]    [Pg.65]    [Pg.155]    [Pg.316]    [Pg.481]    [Pg.216]    [Pg.105]    [Pg.367]    [Pg.11]    [Pg.415]    [Pg.97]    [Pg.69]    [Pg.155]    [Pg.25]    [Pg.196]    [Pg.159]   
See also in sourсe #XX -- [ Pg.151 ]




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Amalgam

Amalgam, aluminum potassium

Amalgamated

Amalgamators

Amalgamism

Amalgamization

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