SUBJECTS chlorates

Ferrous Sulfdte Titration. For deterrnination of nitric acid in mixed acid or for nitrates that are free from interferences, ferrous sulfate titration, the nitrometer method, and Devarda s method give excellent results. The deterrnination of nitric acid and nitrates in mixed acid is based on the oxidation of ferrous sulfate [7720-78-7] by nitric acid and may be subject to interference by other materials that reduce nitric acid or oxidize ferrous sulfate. Small amounts of sodium chloride, potassium bromide, or potassium iodide may be tolerated without serious interference, as can nitrous acid up to 50% of the total amount of nitric acid present. Strong oxidizing agents, eg, chlorates, iodates, and bromates, interfere by oxidizing the standardized ferrous sulfate. 

The invention of percussion compositions for igniting powders is usually attributed to Forsyth [5]. In 1805 he employed pellets composed of a mixture of potassium chlorate and combustible materials, coated with wax to render them safer to handle, but even so they were still dangerous since the mixture was sensitive to friction. The first ignition caps were invented in the early nineteenth century. In these caps the ignitable composition was enclosed in a casing of brass or copper. This invention cannot be traced with any certainty to any individual. The literature on the subject names several chemists including Bellot and Egg in 1815 [5]. 

Such evidence of rotation of the plane of polarization is not likely to be detected in microscopic crystals unless the specific rotation is exceptionally large. The phenomena mentioned above are usually exhibited only by crystals at least several millimetres thick. Suitable subjects for observation are sodium chlorate (cubic), quartz (trigonal, uniaxial), and cane sugar (monoclinic, biaxial). 

Marin(Ref 1) observed that by dissolving Pb chlorate in hot glycerin, a deposit of wh crysts formed, after cooling the soln,which when separated washed with ale constituted a very powerful detonating substance. It exploded violently when subjected to either heat or shock and was proposed for use in various primary compns for detonators, and in pyrotechnics... 

Perchlorates in mixtures with reducing materials are more stable than the corresponding chlorates and are not as subject to dangers from the presence of free acids. Nevertheless, it should not be assumed that all perchlorate mixtures are safe. A perchlorate mixture can be initiated by friction, impact, or spark at energies which cannot be considered safe some of these mixtures are extremely dangerous (Ref 42)... 

B) Destruction of substances contg chlorates or perchlorates but no NG, NC or aromatic nitrocompds can be conducted by the methods described in A, but with some modifications. When expls are drowned in still waters (such as in tanks), the w should not be allowed to evaporate, because dry salts are subject to spontaneous combustion, especially in the presence of org compds. As perchlorates are rather insol in cold w, hot w should be used... 

Stars which contain aluminum are known as electric stars because of the dazzling brilliancy of their light, which resembles that of an electric arc. Stars which contain chlorate and sulfur or antimony sulfide or arsenic sulfide or picric acid are dangerous to mix, likely to explode if subjected to too sudden shock, and unsafe for use in shells. They are used in rockets and Roman candles. Perchlorate compositions, and chlorate compositions without sulfur, sulfides, and picric acid, will tolerate considerable shock and are used in aerial bombshells. 

Lead, Copper, Zinc.—500 or 1000 c.c. are evaporated to small volume, treated with excess of hydrochloric acid and then, while heated on a water-bath, wtili small quantities of potassium chlorate until the liquid is as nearly colourless as possible. This liquid, which contains any of the above metals present, is diluted with water, heated, and subjected to the action of a current of hydrogen sulphide. Any precipitate, which will contain lead and copper sulphides, is collected on a small filter, while the filtrate is tested for zinc according to (c). The precipitate, washed with hydrogen sulphide solution and dried, is ignited with the filter in a porcelain dish. The residue is taken up in a little nitric acid (D i>2), gently heated, diluted with a little water and filtered into a porcelain dish, the filtrate being used for the detection of lead as in (a) and for that of copper, as in (b). 

Metal Halogenates. Dry, finely divided mixtures of red or white phosphorus and chlorates, bromates, or iodates of barium, calcium, magnesium, potassium, sodium, or zinc explode when subjected to friction, impact, or heat. Mixtures of potassium iodate with white or red phosphorus react violently or explosively on addition of a small quantity of water.16... 

The achiral inorganic ionic sodium chlorate (NaClOs) and sodium bro-mate (NaBrOs) crystallize in enantiomeric forms belonging to the P2i3 space group for which the same crystal structures exhibit opposite optical rotation [89]. The levo-(Z) and dextrorotatory (d) crystals can be obtained in equal proportions [90]. The chiral ionic crystals of NaClOs and NaBrC>3 were subjected to asymmetric autocatalysis as the initial seed of chirality to study the correlation between the organic compound with high ee and the chiral inorganic crystal composed of achiral ionic components. 

Concentration of the mother liquor with addition of small quantities of sodium chlorate facilitates the isolation of a second crop of the hexachlorometallate, but the product is subject to increasing contamination by sodium salts. 

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