Mercuiy oxide

Another type of battery is the mercuiy batteiy often formerly used in pocket calculators. The mercuiy battery has a zinc electrode while mercuiy oxide HgO are oxidised in the basic environment consisting of typically KOH and Zn(OH)2. The figure below shows the set-up of the mercuiy diy cell batteiy. 

Mercuiy embritdes both pure and alloyed aluminum, decking the tensile stress by some 20%. The fatigue life of 7075 aluminum alloy is reduced in mercury, and brittle-to-ductile transition occurs at 200 °C (390 °F). Additions of gallium and cadmium to mercury increase the embrittlement of aluminum. Delayed failure of LME occurs in mercuiy. Dewetting of aluminum by mercury has been found to inhibit embrittlement dewetting can be caused by the dissolution of aluminum by mercuiy, oxidation of fine aluminum particles by air, and formation of aluminum oxide white flowers at the aluminum/mercury interface. 

Mercury. In recovering mercuiy from cinnabar ores, the ore is crushed to minus 1.5 cm and fed to rotary Idlns, where it is calcined to over 800 K. Since the mercuiy exists as mercuric siilfide (HgS), the sulfur is oxidized to SO9 and the mercuiy vaporized. The gases are passed through cooling chambers, where the mercuiy condenses and is collected. Mercuiy vaporizes at 625 K. 

C04-0067. When HgO is heated, it decomposes into elemental mercuiy and molecular oxygen gas. If 60.0 g of Hg is obtained from 80.0 g of the oxide, what is the percent yield of the reaction ... 

Mercuiy(II) oxide, Nitric acid MRH Mercury(II) oxide 1.59/tr. 

Dbnerciuy dicyanide oxide, 0983 Dimetbybnercuiy, 0907 Dipbenybnerciuy, 3480 Dipropybnerciuy, 2537 2-Hydroxyetbybnercuiy(ll) nitrate, 0857 Mercury(ll) acetylide, 0975 Mercuiy(II) amide chloride, 3999 Mercury(l) azide, 4612... 

A naturally occurring alloy of silver with mercuiy, also referred to as mercurian silver, silver amalgam, and argental mercuiy. The natural amalgam crystallizes in the isometric system hardness. 3-3.5 sp gr, 13.75-14.1 luster, metallic, color, silver-white streak, silver-white opaque, Amalgam is found in Bavaria. British Columbia. Chile, the Czech Republic and Slovakia, France, Norway, and Spain. In some areas, it is found in the oxidation zone of silver deposits and as scattered grains in cinnabar ores. 

Dibenzosubeiyl alcohol reacts in 60% yield with cysteine to give a thioether that is cleaved by mercuiy(II) acetate or oxidized by iodine to cystine. The dibenzo-suberyl group has also been used to protect —OH, — NH2, and — C02H groups.1... 

Winstein showed that the solvolysis of crotylmercury(II) acetate under kineticalfy contrtdled conditions gives >99.5% of a-methylallyl acetate (equation 13)." Subsequent work indicated that both the solvolysis of cinnamylmercury(n) acetate and the mercuiy(II) acetate oxidation of allylbenzene give ca. 60% ciimamyl acetate (35) and 40% a-phenylallyl acetate (36 equation 14)." An equilibrium exists between (35) and (36) favoring the primary ester which constitutes >99.5% of the equilibrium mixture at 75 C. Oxidation of a range of bodi 1- and 2-alkenes under kinetically controlled conditions exclusively gave the secondary allylic esters. 

A fine example demonstrating the use of an arylboron inteimediate was reported by Santaniello et al As part of a project aimed at evaluating the biological activity of 2-and 4-substituted estrogens a convenient synthesis of 2-hydroxyestradiol was needed. Classical electrophilic oxidations usually lead to equimolar amounts of 2- and 4-isomers which are not easy to separate, and thus a method for regioselective hydroxylation was required. 3-Methoxyestra-l,3,S(10)-trien-17 -yl acetate (12) reacted with mercuiy(II) acetate in dry acetonitrile, and the reaction mixture was then treated wiA saturated aqueous sodium chloride to give the 2-chloromercurio derivative (13) in 80% yield. This inteimediate was then exposed... 

Other transition metal salts mediate in similar oxidations. For example, mercuiy(II) acetate, a milder reagent than LTA, effects a-acetoxylation through a comparable mechanism. However the corresponding yields for these processes are poor. 3,3-Dimethylcyclohexanone, for example, is oxidized to Ae a-acetoxy derivative in only 14% yield. The p,7-unsaturated ketone, isopugelone, exhibits no oxidation at the a- or a -positions, but affords a product derived from isomerization of the alkene and allylic oxidation. Not surprisingly therefore the reagent has found little synthetic application for this transformation. 

The chemistry of alkynes is dominated by electrophilic addition reactions, similar to those of alkeiies. Alkynes react with HBr and HCl to yield vinylic halides and with Br2 and Ch to yield 1,2-dihalides vicinal dihalides), Alkynes can be hydrated by reaction with aqueous sulfuric acid in the presence of mercuiy(ll) catalyst. The reaction leads to an intermediate enol that immediately isomerizes to yield a ketone tautomer. Since the addition reaction occurs with Markovnikov regiochemistry, a methyl ketone is produced from a terminal alkyne. Allernatively, hydroboration/oxidation of a terminal alkyne yields an aldehyde. 

A hydrosol of tungsten hydroxide is readily produced by the electrolysis of a 2 per cent, solution of sodium tungstate between a mercuiy cathode and a silver anode in a Hildebrand cell. The solution must not be allow ed to become acid, or blue compounds are produced. The hydrosols obtained in this way are clear and transj arent but brown in colour. The addition of potassium chloride causes coagulation, a black powder, resembling the lower oxides of tungsten, being formed. ... 

Iminium ion cycUzations such as the Pictet-Spengler reaction have been widely used in alkaloid chemistry to create a carbon-carbon bond between the carbon a to the basic nitrogen and an aromatic ring. The requisite iminium ions in these reactions are often readily available via the modified Polonov-ski reaction. Although two steps, IV-oxide formation and reaction with trifluoroacetic anhydride, are involved, this approach is often preferable to the reaction of a tertiary amine with mercury(II) acetate, in which it is necessary to destroy the amine-mercury complex at the end of the reaction. In this way the secoheteroyohimbinoidiV-oxide (34) was cyclized selectively to uammigine (35 equation 12). Using mercuiy(II) acetate a nearly equal mixture of (35) and its C-3 P-H epimer tetrahydroalstonine is obtained. 

Equip a 500 ml. three-necked flask with a reflux condenser, a mercuiy-sealed mechanical stirrer and separatory funnel, and support it on a water bath. Attach an absorption device (Fig. II, 8, I, c) to the top of the condenser (1). Place 134 g. (152 ml.) of A.B. benzene and 127 g. of iodine in the flask, and heat the water bath to about 60° add 92 ml. of fuming nitric acid, sp. gr. 1-60, slowly from the separatory funnel during 30 minutes. Oxides of nitrogen are evolved in quantity. The temperature rises slowly without the application of heat until the mixture boils gently. When all the nitric acid has been introduced, reflux the mixture gently for 15 minutes. If iodine is still present, add more nitric acid to the warm solution until the purple colour (due to iodine) changes to brownish-red. 

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