Lead fluorides

Lead fluorides are highly toxic and should be handled with great care. The ACGIH adopted toxicity value for lead compounds as Pb is TWA 0.15 mg/m and for fluorides as F 2.5 mg/m. PbF is prepared by the action of elemental fluorine on very dry Pbp2 at 280—300°C (15). 

Lead Fluoride. Lead difluoiide, Pbp2, is a white oithorhombic salt to about 220°C where it is transformed into the cubic form some physical properties ate given in Table 1. Lead fluoride is soluble in nitric acid and insoluble in acetone and ammonia. It is formed by the action of hydrofluoric acid on lead hydroxide or carbonate, or by the reaction between potassium fluoride and lead nitrate. 

Aqueous hydrofluoric acid can be freed from lead by adding ImL of 10% strontium chloride per KXhnL of acid, lead being co-precipitated as lead fluoride with the strontium fluoride. If the hydrofluoric acid is decanted from the precipitate and the process repeated, the final lead content in the acid is less than 0.003 ppm. Similarly, lead can be precipitated from a nearly saturated sodium carbonate solution by adding 10% strontium chloride dropwise (l-2mL per lOOmL) followed by filtration. (If the sodium carbonate is required as a solid, the solution can be evaporated to dryness in a platinum dish.) Removal of lead from potassium chloride uses precipitation as lead sulfide by bubbling H2S, followed, after filtration, by evaporation and recrystallisation of the potassium chloride. 

Lead chloride is freely soluble in hot aqueous solutions, but lead fluoride is almost insoluble in dilute HE solutions. When the HE concentration reaches about 40%, steel is preferred. 

Lead chromate, 82 Lead dioxide, 82 Lead fluoborate, 82 Lead fluoride, 82... 

Explosive interaction when boron and lead fluoride or silver fluoride are ground together at ambient temperature. 

Leaded zinc oxide, 26 613 Lead electrodes, 3 408, 430 Leaders, R D, 21 621 Lead fluoride, 14 784... 

PbF2 LEAD FLUORIDE 797.7308 -6.5142E+04 -2.6816E+02 8.0837E-02... 

Synonyms lead fluoride lead(ll) fluoride plumhous fluoride... 

Elemental composition Pb 84.50%, F 15.50%. The compound can be identified from its physical properties and x-ray measurement. Lead may be analyzed by various instrumental techniques (See Lead). Fluoride ion may be determined by dissolving a minute quantity of the compound in water (the compound is slightly soluble in water) and analyzing the solution by ion chromatography or hy fluoride-ion selective electrode. 

When its aqueous solution is mixed with hydrofluoric acid, lead fluoride precipitates out ... 

Diisodecyl Phthalate Latex, Liquid Synthetic Lead Arsenate Lead Fluoride Litharge... 

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