Compounds of Bismuth

Bismuthides. Many intermetaUic compounds of bismuth with alkafl metals and alkaline earth metals have the expected formulas M Bi and M Bi, respectively. These compounds ate not saltlike but have high coordination numbers, interatomic distances similar to those found in metals, and metallic electrical conductivities. They dissolve to some extent in molten salts (eg, NaCl—Nal) to form solutions that have been interpreted from cryoscopic data as containing some Bi . Both the alkafl and alkaline earth metals form another series of alloylike bismuth compounds that become superconducting at low temperatures (Table 1). The MBi compounds are particularly noteworthy as having extremely short bond distances between the alkafl metal atoms. 

Determination of silver as chloride Discussion. The theory of the process is given under Chloride (Section 11.57). Lead, copper(I), palladium)II), mercury)I), and thallium)I) ions interfere, as do cyanides and thiosulphates. If a mercury(I) [or copper(I) or thallium(I)] salt is present, it must be oxidised with concentrated nitric acid before the precipitation of silver this process also destroys cyanides and thiosulphates. If lead is present, the solution must be diluted so that it contains not more than 0.25 g of the substance in 200 mL, and the hydrochloric acid must be added very slowly. Compounds of bismuth and antimony that hydrolyse in the dilute acid medium used for the complete precipitation of silver must be absent. For possible errors in the weight of silver chloride due to the action of light, see Section 11.57. 

Bismuth is flammable as a powder. The halogen compounds of bismuth are toxic when inhaled or ingested. Some of the salts of bismuth can cause metallic poisoning in a manner similar to mercury and lead. 

On the other hand, the binary compounds of sodium with zinc, cadmium, and mercury, or with tin and lead, have no such analogies with one another. The sodium compounds of bismuth and antimony are analogous, but the characteristics of these latter elements approximate to those of the metalloids,... 

Bismuth arsphenamine sulphonate (Bismarsen , Fig. 9) a yellow powder readily soluble in water, was first prepared by Raiziss in 1924 [70]. Stokes and Chambers [71] were the first to use the drug clinically, giving two injections a week for 14 weeks. Four such courses separated by intervals of a fortnight were administered in all. Nevertheless the effects were slow compared with the arsphenamines, although the tonic effect was greater and the side effects less numerous. Relapses, particularly in the central nervous system (CNS) were more frequent. Consequently, Rayburn and Boyd emphasized the fact that some individuals with neurosyphilis who were intolerant to arsenic in any other form could nevertheless tolerate it in the form of Bismarsen [72]. The low toxicity, the tonic effect, and the ease of administration were the chief advantages in favor of Bismarsen . The other compounds of bismuth with arsenic were not extensively tested in humans. 

The oxides c f bismuth are basic, forming salts such as bismuth chloride, BiCl3- HoO, and bismuth nitrate, 3i(N0 )3 5H.,0. These salts when dissolved in water hydrolyze, and precipitate the corresponding bismuthvl compounds, BiOCl and Bi(OH), NO (or BiONOg-HoO). The compounds of bismuth have found little use bismuthyl nitrate and some other compounds are used to some extent in medicine. 

Bismuth, its properties, occurrence in nature, and use in alloys. Compounds of bismuth bismuth trichloride, bismuth nitrate, bismuthyl chloride, bismuthyl nitrate. 

Syntheses and uses of isotopicaliy labelled compounds of bismuth, antimony... 

The radiochemistry of organometallic compounds of bismuth containing aromatic radicals has been investigated by Nefedov and coworkers. ... 

On the other hand, the uses of nonorganic compounds of bismuth in alloys, metallurgical additives and chemicals are still increasing, especially in pearlescent pigments for cosmetics and plastics, and in varistors and ceramic capacitors. 

M. Zielinski and M. Kanska, Synthesis and Uses of Isotopically Labelled Compounds of Bismuth, Antimony and Arsenic, Chap. 15 in The Chemistry of Organic Arsenic, Antimony and Bismuth Compounds (Ed. S. Patai), Wiley, Chichester, 1994. 

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