Lithium hydrogen sulphate

Of particularly high selectivity is the method for trace water concentration on a column containing salts that form crystal hydrates (e.g., lithium chloride, calcium chloride, sodium hydrogen sulphate), which readily lose water when heated [70]. To increase the sensitivity water was converted into carbon monoxide, which could subsequently be hydrogenated to methane and detected with a flame-ionization detector. 

An analysis based on this formalism has been given for lithium hydrazinium sulphate, LiNjHjSO. This compound crystallizes in an orthorhombic space group, with the NH2 of the hydrazinium cation hydrogen bonded into an extended chain parallel to the crystallographic c-axis and the hydrogen bonded to the Li04 and SO4 tetrahedra. 

Protonic conduction is verified if hydrogen is evolved at the cathode in an electrolysis experiment with a hydrogen source at the anode. This has been used very elegantly by Kreuer, who used the blue colouring of tungsten bronzes when hydrogen is intercalated as a proof of proton conduction in lithium hydrazinium sulphate, HUAs and HUP. Several other workers have used the formation of hydrogen as a proof of proton conduction (Murphy (1964), Takahashi et al. (1976,1979) Chandra (1985)22 Iwahara et al. (1986) ). 

For the bromination of benzoic acid, the rate increased more rapidly than [H+] at high mineral acid concentrations and apparently depended on the acidity function ho rather than [H+]. Neutral salts such as disodium hydrogen phosphate, lithium and sodium sulphates also increased the rate due either to a positive salt... 

When hot, ammonia and compounds, which contain nitrogen-hydrogen bonds eg ammonium salts and cyanides react violently with chlorates and alkaline perchlorates. Diammonlum sulphate, ammonium chloride, hydroxyl-amine, hydrazine, sodamide, sodium cyanide and ammonium thiocyanate have been cited. So far as hydrazine is concerned, the danger comes from the formation of a complex with sodium or lithium perchlorate, which is explosive when ground. Many of these interactions are explosive but the factors which determine the seriousness of the accident are not known. 

Chlorotrimethylsilane (2.7 g, 25 mmol) (1) (CAUTION) is added to a solution of lithium bromide (1.74g, 20 mmol) in dry acetonitrile (20 ml) (2) with good stirring under a nitrogen atmosphere. Cinnamyl alcohol (1.34 g, 10 mmol) is then added and the reaction mixture heated under reflux for 12 hours. The progress of the reaction is monitored by t.l.c. on silica gel plates with hexane as the eluant. On completion of the reaction (12 hours), the reaction mixture is taken up in ether (50 ml), washed successively with water (2 x 25 ml), sodium hydrogen carbonate solution (10%, 50 ml) and finally brine, and dried over anhydrous sodium sulphate. Evaporation of the ether affords the pure bromide in 93 per cent yield. The product may be recrystallised from ethanol and has m.p. 31-32 °C CAUTION this compound is lachrymatory. 

Method B.104 In a 1-litre flask equipped with a condenser, a thermometer and a dropping funnel is placed 0.3 mol of lithium aluminium hydride (CAUTION, see Section 4.2.49, p. 445) in dry ether (300 ml). A nitrogen atmosphere is maintained throughout the reaction. To this stirred solution 0.45 mol of ethyl acetate is added over a period of 75 minutes maintaining the temperature at 3-7 °C. The reaction is stirred for an additional 30 minutes. To this solution at —10 °C is added 29.1 g (0.3 mol) of hexanenitrile in 5 minutes. The reaction temperature rises to 12°C in 10 minutes with the formation of a viscous solution. It is allowed to stir for another 50 minutes at 3 °C. The reaction mixture is decomposed by the addition of 300 ml of 2.5 m sulphuric acid. The ether layer is separated and the aqueous layer is extracted with ether. The combined ether extracts are washed with sodium hydrogen carbonate solution and water and dried over anhydrous sodium sulphate (1). 

Lithium chloride, LiCl.—The anhydrous salt is obtained by evaporating to dryness in a current of hydrogen chloride or in presence of ammonium chloride the solution formed by dissolving the carbonate in hydrochloric acid, or decomposing the sulphate with barium chloride.4 Bogorodsky 5 has isolated three hydrates at very low temperatures the trihydrate, LiCl,3H20, is deposited in small needles at —15° C. the dihydrate, LiCl,2H20, crystallizes in cubes and at 12-5° C. octa-hedra of the monohydrate, LiCl,H20, are formed. At about 98° C. the anhydrous salt separates. 

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