Calcium sulfate charge

A. 2,2-Dichloronorbornane. A 1-1., round-bottomed flask equipped with a mechanical stirrer and a calcium sulfate drying tube is charged with 91.3 g. (0.665 mole) of phosphorous trichloride and 90.0 g. (0.817 mole) of norcamphor (Note 2). The solution is stirred and cooled to 0° in an ice-salt bath, then 193 g. (0.927 mole) of phosphorous pentachloride is added in portions... 

Phosphate rock is converted into usable chemicals by two methods. In the first, the rock is -charged to an electric furnace with silica and coke to produce elemental phosphorus. The phosphorus then is converted into phosphoric acid and other compounds. In the second, the phosphate rock is reacted with sulfuric acid in a medium of phosphoric acid and calcium sulfate crystals to form dilute, impure phosphoric acid, The acid is separated and used to make fertilizers. This is known as the wet process method.15... 

An interesting case in mineral equilibria is the presence in a soil-water system of two minerals with a common ion. An example of such a case is barium sulfate (BaS04) plus calcium sulfate (CaSO. Which mineral would be controlling SOj- in the system Two conditions would need to be met in such a system one is mass-balance while the second is charge balance. The mass-balance is given by... 

D. a-Allyl- -bromoethyl ethyl ether. The same apparatus is used as in the preparation of allyhnagnesium bromide. The flask is charged with an amount of the Grignard solution (part C) equivalent to 2.78 moles of allylmagnesium bromide (or chloride) and cooled in an ice bath. A solution of 580 g. (2.5 moles) of a,j3-dibromoethyl ethyl ether (part B) in an equal volume of anhydrous ether is added slowly with stirring over a period of 3-4 hours. The mixture is allowed to stand overnight and is then hydrolyzed with 75 ml. of 20% acetic acid followed by 500 ml. of water. The ether layer is separated, washed with four 100-ml. portions of 10% aqueous sodium bicarbonate solution followed by four 100-ml. portions of saturated aqueous sodiiun chloride solution, dried over 100 g. of anhydrous calcium sulfate, and distilled under reduced pressure. The yield of colorless a-allyl- Q-bromoethyl ethyl ether is 370-396 g. (77-82% based on the 0 ,/3-dibromoethyl ethyl ether), b.p. 72-75°/21 mm., 1.4600-1.4606. 

All glassware was flame-dried and cooled in a desiccator charged with anhydrous calcium sulfate. Once completely cooled, the glassware was quickly assembled and purged with nitrogen. 

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