Mercury compounds properties

The toxic effects of mercury and mercury compounds as well as their medicinal properties have been known for many centuries. In the first century AD, Pliny indicated the use of mercuric sulfide (cinnabar or vermilion) in medicine and in cosmetics. This compound was probably known to the Greeks in the time of Aristotle (13). 

The corrosion reactions may be slowed down by using zinc alloys (with lead and cadmium, also improving the mechanical properties of zinc to simplify the production process) instead of the pure metal, or by amalgamating the inner surface of the can by adding a small amount of a mercury compound to the electrolyte. 

Bacterial resistance to biocides (Table 13.2) is usually considered as being of two types (a) intrinsic (innate, natural), a natural property of an organism, or (b) acquired, either by chromosomal mutation or by the acquisition of plasmids or transposons. Intrinsic resistance to biocides is usually demonstrated by Gram-negative bacteria, mycobacteria and bacterial spores whereas acquired resistance can result by mutation or, more frequently, by the acquisition of genetic elements, e.g. plasmid- (or transposon-) mediated resistance to mercury compounds. Intrinsic resistance may also be exemplified by physiological (phenotypic) adaptation, a classical example of which is biofilm production. 

Mercury(IF) formohydroxamate N Hg(ONHCO.H)2 or Hg(ON=CHOH)2 Urbanski, 1967, Vol. 3, 158 It possesses detonator properties. See Other MERCURY COMPOUNDS, N-O COMPOUNDS C2H4HgN204... 

Methyl and ethyl mercury compounds have similar toxicological properties, and there is no sharp demarcation between acute and chronic poisoning. Once a toxic dose has been absorbed and retained for a period of time, functional disturbances and damage occur. The latency period for a single toxic dose may vary from one to several weeks longer latency periods on the order of years have been reported for chronic exposures. ... 

The scientific community provided much of the original impetus for improved environmental protection in Sweden. Swedish scientists, for instance, focused attention on the health hazards from organic mercury compounds used in agriculture several years before the Minimata poisonings in Japan brought those problems to the attention of the rest of the world.1 The Swedish chemist Soren Jensen was the first to describe the bioaccumulation properties of PCBs, and the pioneering radiation and biochemical re-... 

Table 94 Physical Properties of Rhodium-Mercury Compounds...

Furthermore, over the last decade, considerable advances in the characterization of mercury compounds by mercury NMR have been made. The properties of the two naturally occurring NMR-active isotopes of mercury, and ° Hg,... 

Ammonium amalgam (NH4Hgn) [7] is at room temperature a rather unstable compound, which decomposes to ammonia, hydrogen, and mercury, but at temperatures (—40 C) below the melting point of mercury the ammonium mercury may be stable for several minutes the ammonium mercury has properties akin to the quaternary ammonium mercury compounds (R4N (Hg5) ). 

Information regarding the physical and chemical properties of mercury compounds is located in Table 3-2. Mercuric acetate has been included as an organic form of mercury. However, the bonds of the salt are not covalent and, in aqueous solution, the mercury behaves like an inorganic form. 

Physical and Chemical Properties. The physical and chemical properties of metallic mercury and its inorganic and organic compounds have been well characterized to permit estimation of their environmental fate (Lewis 1993 Merck 1989 NFPA 1994 Osol 1980 Spencer and Voigt 1968 Verschueren 1983 Weast 1988 Weiss 1986). Most values are available for the log Kow, log Koc, Henry s law constant, vapor pressure, and solubility in water. Experimental data exist that allow characterization of the environmental fate of metallic mercury and inorganic and organic mercury compounds in a variety of environmental media. 

Some cyclic orz/io-carboranyl mercury compounds CB H (T Ig, . where X = 3 or 4, have been prepared and shown to have anion-binding properties (Fig. 3.15)The 12-mercuracarborand-4 [CBioHioCHg]4, for example, can bind one chloride ion at its center (12) or two iodide ions above and below the 12-membered (C2Hg)4 ring (13), while two 9-mercuracarborand-3 (C2I Ig) rings (14) are capable of sandwiching one iodide anion. ... 

Wool fibres may be subjected to fullering - the fibres are treated with an appropriate agent (traditionally mercury compounds were used), which causes the individual scales on the fibre to stand proud of the surface, causing adjacent fibres to become entangled, and increasing the bulk of the material. The process can be employed to make non-woven woollen textiles (i.e. felt), but is also employed to modify the properties of fibres used for yarns and fabrics, and can give a durability to wool fabrics that is not found in the individual fibres. 

Compounds with high diuretic potency resulted from the observation in 1919 that an antisyphilitic organic mercury compound, merbaphen, also had strong diuretic properties. It was demonstrated the next year that the drug increased the excretion rate of Na+ and Cl" (i.e., it was saluretic). 

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