Lead Perchlorate

The mixture of diastereomers has been separated into its two principal components by Izatt, Haymore, Bradshaw and Christensen who had previously identified the two principal diastereomers as the cis-syn-cis and cis-anti-cis isomers. Their previous separation technique involved a protracted chromatography on alumina but the new method relied upon the difference in water solubility between the lead perchlorate and hydroniur perchlorate complexes. The lead perchlorate complex is essentially insoluble in aqueous solution and precipitates from it. Using this method, one may obtain 39% of the high-melting polymorph (mp 83—84°) and 44% of the low-melting compound (mp 62—63°). Note that the former also exists in a second crystalline form, mp 69—70°. 

See other endothermic compounds, halogen oxides 4108. Lead perchlorate... 

Willard, H. H. et al., J. Amer. Chem. Soc., 1930, 52, 2396 A saturated solution of anhydrous lead perchlorate in dry methanol exploded violently when disturbed. Methyl perchlorate may have been involved. 

Lead nitrate complexed with EDTA and lead perchlorate and sodium sulphide have been used for PbS ECALE-deposition.158159 The films were cubic and highly (200) oriented, and AFM images showed the same cubic structure.158159 PbSe films were also cubic, and the band gap of a film after 50 deposition cycles was 8000cm-1.160 PbSe/PbTe superlattices, with 4.2-nm and 7.0-nm periods, have been grown by ECALE.161 The (111) reflection in the XRD pattern showed a first-order satellite peak and one second-order peak, indicating the formation of the superlattice. AFM images of the superlattice structure showed a small amount of three-dimensional growth.161... 

Lead dioxide Lead perchlorate Lithium chlorate Lithium hypochlorite Lithium perchlorate Lithium peroxide Magnesium bromate Magnesium chlorate Magnesium perchlorate Magnesium peroxide Manganese dioxide Mercurous chlorate Mono-(trichloro)-tetra-(mono-potassium dichloro)-penta-s-triazinetrione... 

Indium(I) perchlorate, 4014 Iron(II) perchlorate, 4062 Iron(III) perchlorate, 4134 Lead perchlorate, 4108 Lithium perchlorate, 4021 Magnesium perchlorate, 4084 Manganese(II) perchlorate, 4088 Mercury(II) perchlorate, 4078... 

Total sulfate may be determined in a 50 50 water-methanolic formaldehyde solution by titration with standardized 0.1//lead perchlorate. Endpoint detection is effected using a combination lead ion-selective electrode, and the level of sulfate is typically 13.8 wt % [14]. 

Inorganic lead compounds such as PbO, Pb02, Pb304, PbS, lead molybdate and lead perchlorate 2) Lead salts of organic adds such as 2,4-dihydroxy benzoic add, salicylic add, acetyl salicylic add and methoxy propionic add i) Effective with propellants of cal. val. less than 900 cal. g 1 ii) Lead salts of aromatic adds are effective with propellants of higher cal. val. [237]. 

The extremely low solubility of lead phosphate in water (about 6 x 10 15m) again suggests potentiometric analysis. Selig57,59 determined micro amounts of phosphate by precipitation with lead perchlorate in aqueous medium. The sample was buffered at pH 8.25-8.75 and a lead-selective electrode was used to establish the end-point. The detection limit is about 10 pg of phosphorus. Anions which form insoluble lead salts, such as molybdate, tungstate or chromate, interfere with the procedure. Similar direct potentiometric titrations of phosphate by precipitation as insoluble salts of lanthanum(III), copper(II) or cadmium(II) are suggested, the corresponding ion-selective electrodes being used to detect the end-point. 

Kaneto et al.523) have made measurements on the diffusion of lead perchlorate in polythiophene by following the colour change. They found a diffusion coefficient which varied from 10-1° to I0-12 cm2 s 1, depending upon the applied potential. The complexities introduced by morphological heterogeneity, counter-ion motion and solvent effects mean that further studies will be required to determine the relative importance of factors affecting diffusion in these materials. 

Hydrogen peroxide Oxygenated compounds MRH 5.98/76 Lead perchlorate Methanol Nitric acid Alcohols (reference 6) MRH 5.31/70 Sodium hypochlorite Methanol MRH 2.47/90... 

A saturated solution of anhydrous lead perchlorate in dry methanol exploded violently when disturbed. Methyl perchlorate may have been involved. 

Indium perchlorate, 4008 Iron(II) perchlorate, 4056 Iron(III) perchlorate, 4056 Lead perchlorate, 4102 Lithium perchlorate, 4015... 

The chlorates, like the nitrates, are all readily soluble in water lead and silver chlorites, like the corresponding nitrites, are sparingly soluble salts and lead perchlorate is the only salt which does not easily dissolve. As already mentioned, chloric acid is readily decomposed when its aqueous solution is warmed chlorous acid is still less stable but perchloric acid, which may be prepared by distilling together potassium perchlorate with concentrated sulphuric acid, is relatively stable, seeing that it can be distilled without decomposition. It is an oily liquid, with acid taste it is apt to explode when brought into contact... 

Such methods are wet oxidation of pulp followed by estimation of sulfate by precipitation of barium sulfate (Canadian Pulp and Paper Association Standard G28 1970), X-ray fluorescence spectroscopy (Rivington 1988, Kibblewhite et al. 1987), and combustion of pulp followed by analysis of sulfur as sulfur dioxide or as sulfate. The sulfur dioxide evolved is determined by iodometric titration (Canadian Pulp and Paper Association useful method G.7U, March 1959). Sulfate can be determined by titration with barium chloride (Ora 1960), back-titration with sulfuric acid after addition of barium perchlorate (Aldrich 1974), potentiometric titration with lead perchlorate using an ion-selective electrode (Ross and Frant 1969), or ion chromatography (Douek and Ing 1989). 

FIGURE 2.26 SEM picture of montmorillonite treated with 5e-4 mol/dm3 lead perchlorate solution. Lower left side morphology of the sample made by backscattered electrons. Lower right side lead map made by characteristic x-ray photons. Upper morphology of the sample made by backscattered electrons, enlarged from site No. 2. 

FIGURE 2.28 Atomic force microscopic (AFM) picture of a mica plate immersed into the suspension of Ca-montmorillonite and 5.10-4 mol dm-3 lead perchlorate solution. 

Ten separate portions of adsorbent of 0.146 g (5.0 X 10 eq) each were washed to constant conductivity with deionized water in order to remove any adsorbed ions. They then were each placed in 50 mL of solution to give a CEC per unit volume of 1.0 X 10 eq L which contained either 1.0 X 10 or 5.0 X 10 M lead perchlorate in C02 free deionized distilled water. The pH was then adjusted, by the addition of 1.0 normal sodium hydroxide or perchloric acid as appropriate, to values of approximately 2, 3, 4,... 

SYNS LEAD DIPERCHLORATE LEAD PERCHLORATE LEAD PERCHLORATE, soUd or solution pOT) LEAD(2+) PERCHLORATE... 

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