Salts of Lead

With sparingly soluble salts of lead, the compactness of the deposits may be strongly influenced by the concentration of the relevant anion. Very low concentrations frequently resulting in imperfect coatings. 

Gasiorek K, Bauchinger M. 1981. Chromosome changes in human lymphocytes after separate and combined treatment with divalent salts of lead, cadmium, and zinc. Environ Mut 3 513-518. 

We generally associate saltiness with salts. But not all salts are salty. For example, most salts of lead are sweet. The Romans were accustomed to adding lead salts to their wine to add sweemess. Unhappily, lead salts are also toxic. To what extent lead poisoning from their wines contributed to the downfall of the Roman Empire is not known. But it certainly did nothing positive for the heaim of the Romans of the time. 

Since the late 1960 s problems related to ccxitaminaticxi of fish and shellfish have been recognized. The problem compounds share one characteristic biopersistence. Compounds such as various salts of lead or mercury have contaminated shellfish or fish living in either fresh or salt water. Chlorinated compounds such as DDT, PCB and dioxins have been found in fish living in fresh water rivers and lakes and to some extent in the Baltic and Mediterranean Seas (25). 

Although an insoluble salt of lead, the compound exhibits low-to-mod-erate systemic effects from ingestion in humans. The effects are gastrointestinal contractions, jaundice, convulsions, nausea or vomiting, and degenerative changes in the brain (Lewis (Sr.), R. J. 1996. Sax s Dangerous Properties of Industrial Materials, 9 i ed. New York Van Nostrand Reinhold). 

Lead sulfate precipitates when an aqueous solution of lead nitrate or other soluble salt of lead is treated with sulfuric acid. 

Stabanate A proprietary of Olin-Mathieson Chemical Co applied to the double salt of Lead Styphnate Lead Nitroaminotetrazole. It was patented by E.A. Staba, USP 3310569(1967)... 

USP 3310569(1967) CA 67, 2273(1967) (Initiating device contg double salt of Lead Styphnate and Lead Nitroaminotetrazole. 

Flo. 53. Loss of water of crystallization by the neutral salt of lead styphnate at various temperatures 1—145°C,2—135°C,5— 115°C, 4—hydration curve at 30°C, according... 

Double Salt of Lead Nitroaminotetrazole and Lead Styphnate. USP 3310569 of March 21,... 

Double salt of lead nitroaminotetrazole and lead styphnate 5 D1541... 

The shoots are taken off, put into n small carriage, and convoyed on a tramway to tho departments of tho work where the pairing of tho salt of lead from the unoxidised portions of the metal takes place. Since the latter is the highest part of the machinery in the area where the cleansing, grinding, and other operations arc effected, the railway mentioned is on the second story of the establishment.. 

Chromate of Lead—TbO, Or Of—chrome yellow.— When chromate of potassa is added to a soluble salt of lead, both solutions being hot, a fine colored anhydrous precipitate is obtained if the solutions are cold, tho precipitate wilt bo pale yellow, and will contain an equivalent of water. 

When present in considerable quantity in a gaseous mixture, hydrogen sulphide can be estimated by the increase in weight of suitable absorption tubes, containing, for example, moist granulated salts of lead or copper.8 More convenient, however, is the oxidation of the gas to sulphuric acid by passage through bromine water or other suitable... 

K. Bahadur, Study of Some Double Salts of Lead Useful as Initiating Explosives by Thermogravimetry and Thermometric Titrations , Symp-ChemProblConnectedStabExpls[Proc], 3rd 1973 (Pub 1974), J. Hansson, Ed, CA 83, 30455 (1975) [The author reports that Lead-5,5 -Diazoaminotetrazolate Styphnate was found to be superior as an initiator expl to other double complexes with azotetrazolic acid or 5-nitra-minotetrazolic acid investigated, and it is recommended as an ideal replacement for Fb Azide... 

In addition, metallic salts of lead, cobalt, or manganese can be dissolved in oil to accelerate drying. 

Table 1 lists two common metals, lead and mercury. The highly teratogenic organic compounds of these metals are not ordinarily handled in the undergraduate laboratory. Inorganic salts of lead and mercury are discussed in the next section. It is only the free elements that are addressed here. 

Lead nitrate is one of the most readily prepared salts of lead, since it is of moderate solubility and can be obtained in well-formed anhydrous crystals, Pb(NOs)2. In it lead appears in its usual state of oxidation, which corresponds to that of the oxide PbO indeed, the salt is actually prepared by treating this oxide (litharge) with nitric acid. 

In an analogous manner salts of lead, PbPtBr4(OH)2.Pb(OH)2 thallium, Tl2PtBr4(OH)2 and mercury, HgPtBr4(OH)2, have been prepared,7 whilst electric conductivity measurements indicate that the sodium salt, Na2PtBr4(OH)a, can exist in solution.7... 

Unfortunately both words were used to describe several different things. "Plumbago" meant graphite, which was easily confused with molybdenum disulphide. "Molybdena" (or molybdaena) also meant graphite, as well as various ores or salts of lead. At certain times and places molybdenite would have been more readily available than graphite, and may well be the subject of some of the early references, but the lack of continuity in the written record makes it impossible to establish when or how the name became more closely associated with molybdenum disulphide. 

The solubility of lead chromate in water is exceedingly small indeed, the chromate is probably the least soluble salt of lead. It is practically insoluble also in dilute acetic acid consequently chromate ions in presence of acetic acid constitute a very delicate test for lead ions in solution. The solubility of lead chromate in water at 25° C. is about 10 grams per litre according to Kohlrausch, but von Hevesy and Paneth obtained the value 1-2 X 10 grams per litre by employing... 

Double salts of lead chromate with alkali chromates have been obtained. The potassium salt, K3Cr04.PbCr04 or KaPb(Cr04)2, is formed as a yellow amorphous precipitate when SO c.c. of a saturated solution of potassium chromate is mixed with 10 c.c. of saturated lead acetate solution. The ammonium salt, (NH4)2Pb(Cr04)2, is prepared similarly, and both salts are decomposed into their components by %vater. 

Double Salt of Lead Nitroaminotetrazole and Lead Styphnate. USP 3310569 of March 21, 1967 of E.A. Staba (to Olin Mathleson Corp) is described in CA 67, 2273(1967)as follows Crystals of the double salt (I) are formed by... 

Metal complex formation can be used to stabilize an otherwise reactive or unstable organic developer, such as hydroquinone or p-phenylenediamine, to permit its incorporation into silver halide emulsion layers or adjacent layers. For example, catechols and hydroquinones can be mixed with several metal salts of lead(II), cadmium or barium and incorporated into emulsion layers. Treating the film with an activator solution containing an anion that forms an insoluble salt of the metal ion (S04 , liberates the organic developer.The structures of the complexes... 

In vain did I endeavor to separate water from the benzoic acid, ° by saturating the crystallized acid with a given quantity of oxide of lead, and therefore could not infer the presence of water of crystallization this analysis farther gave four atoms of oxygen, although I had previously foimd by analysis of the salt of lead that the acid in it saturated three times as much of the oxide as in the neutral benzoate, I was therefore induced since the results did not correspond, to reject this analysis of the crystallized acid. 

In order to prevent the volatilizing of the acid I employed the salt of lead this is the analysis I have described. The result calculated from the corrected atomic weight and compared with your analysis is as follows ... 

It has long been known that the rate of silane homopolymerization is increased by pH or metal salt catalysis and decreased by increased concentration and higher temperature. Most silanes are hydrolyzed most rapidly at pH between 3 and 5. Solution stability depends on the rate of homopolymerization to siloxane polymer. This is affected by pH, the presence of soluble salts of lead, zinc, iron, etc., and silane concentration. A pH in the range of 4 to 5 generally favors the monomeric form and retards polymerization. The formation of homopolymer can be detected as silane loses solubility and forms a gel which is not active in the coupling process. It is, then, desirable to retain silane in the monomeric or dimeric form. In the next two steps a bond is formed with the substrate (e.g., filler). 

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