Heat mercury compounds

Many mercury compounds are labile and easily decomposed by light, heat, and reducing agents. In the presence of organic compounds of weak reducing activity, such as amines (qv), aldehydes (qv), and ketones (qv), compounds of lower oxidation state and mercury metal are often formed. Only a few mercury compounds, eg, mercuric bromide/77< 5 7-/7, mercurous chloride, mercuric s A ide[1344-48-5] and mercurous iodide [15385-57-6] are volatile and capable of purification by sublimation. This innate lack of stabiUty in mercury compounds makes the recovery of mercury from various wastes that accumulate with the production of compounds of economic and commercial importance relatively easy (see Recycling). 

Section II, A, 3)], by conversion into the mercury compound 102 and subsequent heating. Aryne 98 was trapped with tetracyclone and the product (103) was formed in 70% yield. 

Seyferth (7) discovered that phenyl(trihalomethyl)mercury compounds decompose when heated in a solvent giving dihalocarbenes. When the solvent contains a suitable olefin, carbene addition occurs giving 1,1-dihalocyclopropane derivatives. The reaction has the advantage that strong base is not required in the reaction mixture, and base-... 

It explodes if heated above its normal decomposition temperature of 100-110°C. See other mercury compounds, peroxoacid salts... 

In from eight to ten hours up to 10 1. of acetylene are taken up. The colourless intermediate mercury compound very soon begins to separate. After the passing in of acetylene has ceased the whole of the reaction mixture is transferred to a round-bottomed flask and heated on a conical (Babo) air bath, while steam is passed through to decompose the mercury compound. The acetaldehyde liberated distils with the steam. An apparatus similar to that described under (a) is used one receiver containing ether and cooled in a freezing mixture is sufficient. The aldehyde is precipitated from the ethereal solution as aldehyde-ammonia in the manner described above. Yield of aldehyde-ammonia 5-6 g. 

Joseph Priestley (1733-1804) heated mercury with air and formed a red powder (mercuric oxide) that, when heated in a test tube, produced small globs of mercury metal on the inside of the glass tube, as well as a gas that caused other substances to burn more rapidly than they did in air. Priestley did not know it at the time, but he had separated oxygen from the compound HgO. 

The compound also can be made by heating mercury(II) chloride with mercury. The product Hg2Cl2 sublimes and is collected ... 

It is stated that protoxide of mercury ia occasionally adulterated -with minium or red lead, sesquioxide of iron, and powdered brick. Such substances are readily detected by heating the substance to a dull heat the protoxide of meroury sublimes, and leaves the nonvolatile matters in the crucible, or the mercurial compound maybe treated with dilute nitric add, to dissolve the mercurial oxide and should minium be present, a pace-colored binoxide of lead remains together with the other adulterants, if any be present. On adding dilute sulphuric acid to the door liquor obtained in the foregoing, a white precipitate of sulphate of lead falls, corroborative of the existence of a lead compound. 

None of these methods are however, followed in its manufacture, recourse being always bad to the dry process of subliming a mixture.of chloride of sodium and sulphate of mercury, when a chloride of the latter and sulphate of soda are formed, the mercurial compound being expelled by the heat. Thus —... 

The double salt explodes violently if heated. On standing a long time even at room temperature it deteriorates slightly. For preparation of the organic mercury compounds the double salt need not be completely dry. 

Oxygen was first isolated and characterized in the period 1771-1774 by the English chemist Joseph Priestley and the Swedish chemist Karl Wilhelm Scheele. Priestley and Scheele found that heating certain compounds such as mercury(II) oxide generates a colorless, odorless, tasteless gas that supports combustion better than air does ... 

Arsenical or mercury compounds are detected by evaporating a quarter of a litre of the ink and heating the extract with 1-2 c.c. of concentrated sulphuric acid and 5-10 c.c. of fuming nitric acid until nitrous vapours are eliminated, the addition of nitric acid and the heating being repeated until a perfectly colourless liquid is obtained (Rothe). The sulphuric add is then expelled and the residue tested for arsenic and mercury by the ordinary analytical methods. 

Possibly polymeric, it explodes when heated or shocked. See other MERCURY COMPOUNDS, METAL ACETYLIDES... 

Whitmore, 1921, 128 It explodes slightly on heating. See other MERCURY COMPOUNDS See related METAL CYANIDES... 

Magnetic stirrers, 206 Maximum reaction heat, 206 Mek peroxide, 206 Mercury compounds, 207... 

The action of liquid sodium amalgam on trimethylchlorosilane (34a, 34b) or -bromosilane (207) at room temperature results in the exclusive formation of bis(trimethylsilyl)mercury, [(CH3)3Si]2Hg, which is relatively stable to heat. This compound, however, undergoes decomposition on heating at 100°-160° C for a day to give hexamethyldisilane in quantitative yield (9, 34a, 34b, 207). 

First, to produce the mercury component, a pulverized mixture of 50 g of allylcarbamide and 50 g of succinic anhydride is heated for 30 minutes at 110°C. After cooling the fused mass is ground with 50 cc of cold water and the crystalline mass after quick filtering from the liquid is recrystallized from hot water. The white crystalline needles having a MP of 142° to 144°C are allyl-succinyl-carbamide. In order to produce a mercury compound thereof a mixture of 20 g of the allyl-succinyl-carbamide and 30 g of mercury acetate is... 

Dry test All mercury compounds, irrespective of their valency state, form mercury metal when heated with excess anhydrous sodium carbonate. For practical hints see Section III.5, reaction 15. 

Description Three RAM processes are available to remove arsenic (RAM I) arsenic, mercury and lead (RAM II) and arsenic, mercury and sulfur from liquid hydrocarbons (RAM III). Described above is the RAM II process. Feed is heated by exchange with reactor effluent and steam (1). It is then hydrolyzed in the first catalytic reactor (2) in which organometallic mercury compounds are converted to elemental mercury, and organic arsenic compounds are converted to arsenic-metal complexes and trapped in the bed. Lead, if any, is also trapped on the bed. The second reactor (3) contains a specific mercury-trapping mass. There is no release of the contaminants to the environment, and spent catalyst and trapping material can be disposed of in an environmentally acceptable manner. 

---