Azides calcium

The material is impact-sensitive when dry and is supplied and stored damp with ethanol. It is used as a saturated solution and it is important to prevent total evaporation, or the slow growth of large crystals which may become dried and shock-sensitive. Lead drains must not be used, to avoid formation of the detonator, lead azide. Exposure to acid conditions may generate explosive hydrazoic acid [1], It has been stated that barium azide is relatively insensitive to impact but highly sensitive to friction [2], Strontium, and particularly calcium azides show much more marked explosive properties than barium azide. The explosive properties appear to be closely associated with the method of formation of the azide [3], Factors which affect the sensitivity of the azide include surface area, solvent used and ageing. Presence of barium metal, sodium or iron ions as impurities increases the sensitivity [4], Though not an endothermic compound (AH°f —22.17 kJ/mol, 0.1 kj/g), it may thermally decompose to barium nitride, rather than to the elements, when a considerable exotherm is produced (98.74 kJ/mol, 0.45 kJ/g of azide) [5]. 

Calcium, strontium and barium azides are not shock-sensitive, but explode on heating at about 150, 170 and 225 (or 152)°C, respectively. In sealed tubes, the explosion temperatures are higher [1], Although calcium azide is rather mildly endothermic (AH°f (s) +46 kJ/mol, 0.37 kJ/g), it can decompose much more exothermally to the nitride (189.9 kJ/mol, 1.53 kJ/g) than to the elements [2],... 

Calcium azide, 3936 f Carbon disulfide, 0560 Chlorine dioxide, 4042 Chloroacetylene, 0652 Chloryl perchlorate, 4104 Copper(I) azide, 4287 Cyanamide, 0404 Cyanoform, 1383 Cyanogen bromide, 0313 Cyanogen chloride, 0323 Cyanogen fluoride, 0323... 

Caesium azide, 4262 Calcium azide, 3936 Cerium azide, 3966... 

Calcium Azide Hydrazinates. Ca(N3)2 N2H4 and Ca(N3)2 2N2H4 the addn of ale to a soln of Ca(N3)2 in anhyd N2H4, or evapn of such a soln in a vacuum desiccator over sulfuric acid leads to the formation of a 2-hydrazinate. This solvate dissociates rapidly under reduced pressure and/or at higher temps to give the 1-hydrazinate, Ca(N3)2 N2H4 (Ref 1)... 

The explosive properties of sodium, calcium, strontium and barium azides have been investigated at the Chemisch-Technische Reichsanstalt [135]. These azides differ markedly from lead, silver and cupric azides in that they show none of the properties of primary explosives. All three may be ignited by a spark, a glowing wire or the flame of blackpowder. Calcium azide bums most rapidly and has distinctly marked explosive properties. Larger quantities of it may explode when ignited in a closed tin, while strontium and barium merely bum violently. Calcium azide detonates under the influence of a detonating cap. The sodium azide does not decompose in these conditions. The other azides show weak decomposition under the influence of a standard (No. 3) detonator. Their most important properties are tabulated below. 

The spectra of calcium azide explns were photographed by Petrikaln (Ref 6) and the Raman Effect studied by Kahovec Kohlrausch (Ref 13)... 

The azides of the alkaline earths were made by T. Curtius and J. Rissom by dissolving the oxides or hydroxides in dil. hydrazoic acid—say 2-8 per cent. The excess of alkaline earth can be removed by passing carbon dioxide into the boiling soln., and the filtrate cone, by evaporation. There remain colourless, rhombic needles of calcium azide, CaN6 and, according to L. M. Dennis and C. H. Benedict, spherical masses of minute crystals may be formed. The crystals are very hygroscopic and deliquescent. T. Curtius found that the salt does not explode by percussion, but it does so if rapidly heated on a metal plate, and it explodes at about 144°-156°... 

CaNe (c). Wohler and Martin1 measured the heat of decomposition of calcium azide. 

Cadmium Acetylide A71-L Cadmium Amide A169-L Cadmium Azide A526-L Cadmium Azidodithiocarbonate A636-R Cadmium Diazide A526-L Calcium Acetate A28-L Calcium Acetylide A71-L Calcium Azide A527-R Calcium Carbide. See under Acetylides and Carbides A71-R... 

Ammonium hexacyanoferrate(II), 2572 f Arsine, 0100 Azido-2-butyne, 1469 3-Azidopropyne, 1111 cis-Azobenzene, 3478 Azoxybenzene, 3479 Barium azide, 0214 Benzenediazonium nitrate, 2268 Benzotriazole, 2262 Borane, 0135 Bromine azide, 0256 f 3-Bromopropyne, 1087 f 1,2-Butadiene, 1475 f 1,3-Butadiene, 1476 f Buten-3-yne, 1419 f 1-Butyne, 1477 f 2-Butyne, 1478 Cadmium azide, 3951 Cadmium cyanide, 0585 Cadmium fulminate, 0586 Cadmium nitride, 3954 Calcium azide, 3930 t Carbon disulfide, 0557 Chlorine dioxide, 4036 Chloroacetylene, 0648... 

Caesium azide, 4256 Calcium azide, 3930 Cerium azide, 3960... 

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