Sodium chlorate Subject

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). 

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. 

Thus there are two classes of optically active crystals. One, like quartz and sodium chlorate, only shows the effect in the crystalline state. Here the ability to rotate the plane of polarized light is related to the fact that the atoms in the crystal are arranged as right-handed or left-handed spirals or other asymmetric shapes. The second class of optically active crystals contains molecules or ions, such as certain tartrates, that are themselves asymmetric the effect persists even when the crystal melts or is dissolved. More details on this subject are given in Chapter 14. 

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. 

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... 

In some of these, for example, in allergic bronchopulmonary aspergillosis there is evidence to support a type III reaction (Pepys 1977 b). No skin reactions were elicited in either of the two subjects with other oxidizing agents such as potassium permanganate, potassium chlorate, sodium perchlorate, and potassium sulphate. Ammonium persulphate has also been reported to cause urticaria and dermatitis, giving both immediate and non-immediate skin test reactions (Calnan and Shuster 1963). 

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