Periodate, barium sodium

The properties of elements are correlated with their positions in the periodic table. Chemists use the periodic table as an invaluable guide in their search for new, useful materials. A barium sodium niobate crystal can convert infrared laser light into visible green light. This harmonic generation or frequency doubling is very important in chemical research using lasers and in the telecommunications industry. 

Strontium [7440-24-6] Sr, is in Group 2 (IIA) of the Periodic Table, between calcium and barium. These three elements are called alkaline-earth metals because the chemical properties of the oxides fall between the hydroxides of alkaU metals, ie, sodium and potassium, and the oxides of earth metals, ie, magnesium, aluminum, and iron. Strontium was identified in the 1790s (1). The metal was first produced in 1808 in the form of a mercury amalgam. A few grams of the metal was produced in 1860—1861 by electrolysis of strontium chloride [10476-85-4]. 

The same goes for carbon (the accident was caused because carbon was used instead of manganese dioxide, by mistake), sulphur and phosphorus. There was a detonation with carbon. With phosphorus the detonation occurred once the carbon disulphide used to dissolve phosphorus vapourised red phosphorus behaves the same way. The same happened with the potassium chlor-ate/sodium nitrate/sulphur/carbon mixture, which led to a violent detonation as well as with the potassium perchlorate/aluminium/potassium nitrate/barium nitrate/water mixture. In the last case the explosion took place after an induction period of 24h. 

Using the periodic table if necessary, write formulas for the following compounds (a) hydrogen bromide, (b) magnesium chloride, (c) barium sulfide, (d) aluminum fluoride, (e) beryllium bromide, (/) barium selenide, and (g) sodium iodide. 

The removal of inorganic salts from reaction mixtures afforded by polymeric materials may be simply and effectively accomplished by dialysis,166 178 after decomposition of remaining periodate with ethylene glycol130 131 or butylene glycol. 161 170 Alternatively, the iodate and periodate ions may be removed as such, or after reduction to free iodine. The iodate and periodate ions have been effectively precipitated by means of sodium carbonate plus manganous sulfate,6 or by lead dithionate,191 barium chloride,24 192 193 strontium hydroxide194 202 or barium hydroxide,203 204 lead... 

Carbon dioxide is not a common oxidation product in periodate work, but it does appear in the oxidation of ketoses,49 a-keto acids,14,39 and a-hydroxy acids,14 39 and it is often a product23 141 of overoxidation. Carbon dioxide analyses have been carried out using the Plantefol apparatus,49 the Warburg apparatus,14 23 and the Van Slyke-Neill mano-metric apparatus,39 and by absorption in standard sodium hydroxide141 followed by back-titration with acid. A most convenient method is the very old, barium hydroxide absorption scheme.16 The carbon dioxide is swept from the reaction mixture into a saturated, filtered barium hydroxide solution by means of a stream of pure nitrogen. The precipitated barium carbonate is filtered, dried, and weighed. This method is essentially a terminal assay. The manometric methods permit kinetic measurements, but involve use of much more complicated apparatus. 

Detection and determination.—The periodates behave towards reducing agents like the iodates. They are usually but slightly soluble in water and readily soluble in dil. nitric acid. When soln. of sodium periodate are added to barium, strontium, calcium, lead, and silver salts, precipitates of dimesoperiodates are obtained, and the mother liquor has an acid reaction—the silver salt is pale yellow, the others white—silver iodate is also white. The silver precipitate becomes dark red when boiled in water the fresh precipitate is very soluble in ammonia, the dark red... 

If an alkali periodate be treated with a soln. of a barium salt, C. F. Rammelsberg 14 says that the soln. becomes more and more acid with sodium periodate 2Nal04+2Ba(N03)2+H20=Ba2I209+2NaN03+2HN03 but with potassium dimesoperiodate the soln. remains neutral. The voluminous precipitate soon... 

The sodium periodate from 100 g. of iodine (about 225 g.) is suspended in a liter of boiling water containing 10 ml. of concentrated nitric acid (to increase the solubility of the periodate). A moderate excess of barium nitrate (325 g.) dissolved in hot water is added, and the solution is boiled for to 2 hours with vigorous stirring. The solution... 

The preparation conveniently starts with iodine which can be converted through the sodium and barium salts to the acid without drying the intermediate products. From 200 g. of iodine, 302 to 326 g. of periodic acid (about a 90 per cent yield) can be obtained. A run can easily be made in a day. The principal losses are due to the volatilization of iodine in the first step, the solubility of sodium periodate, and reduction of the acid to iodic acid. The barium nitrate and much of the nitric acid are recovered for further use. 

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