Basic Cupric Azide

Cupric Azide, Basic (Anhydrous Cupric Oxyazide), CuO-Cu(Ns)a, mw 227.13, N 37.00% yel solid, expl 203-5° (Ref 11), ignites 245° (Ref 3). Cirulis Straumanis (Ref 11) assigned to it the formula Cu(0H)Ns. Basic cupric azide was first prepd by Wohler ... 

Basic Cupric Azide. See Cupric Azide, Basic v oi i,p A535-L, under Azides... 

Normal cupric azide Basic cupric azides Cu(N3)2 Cu(N3)2-Cu(OH)2 Cu(N3)2-2Cu(OH)2 Cu(N3)2-3Cu(OH)2 Cu(N3)2-8CuO 2.2-2.25 [5] 2.58 [105] 587 [27] Black-brown Yellow-brown Yellow-green Green Blue-green... 

Boiling in water (Wohler and Krupko [80]) leads to hydrolysis with the formation of basic cupric azide. Long-continued boiling causes complete hydrolysis to cupric oxide and free acid. Black cupric azide, Cu(N3)2, when exposed to the action of air for 2 months, is completely converted into a yellow basic salt. This is discussed later. 

Basic cupric azide, Cu(OH)N3, prepared by Wohler and Krupko, is yellow coloured. According to Straumanis and Cirulis it is less sensitive to friction and impact. It is exploded by a 1 kg weight falling from a height of 7-8 cm. Its ignition temperature is the same as that of the neutral salt (203-205°C). 

BASF see Badische aniline-und sodafabrik 2 B4 Bashforth chronograph see Chronographs 3 C308 Basic cupric azide 1 A533 Basic lead acetate 1 A28 Basic lead azide 1 A555... 

F. Martin gave 174° for the temp, of explosion. According to L. Wohler and W. Krupko, basic cupric azide, cupric oxyazide, CuO.CuNg, is formed as a yellow hydrated substance when water with normal cupric azide in suspension is heated to 70°-80° in a current of air freed from carbon dioxide until the calculated quantity of hydrazoic acid has been evolved. It inflames at 245°. L. M. Dennis and H. Isham obtained cupric amminoazide,Cu(NHg)Ns,by shaking freshly precipitated black cupric hydroxide, while still moist, with an excess of hydrazoic acid and washed the precipitate. A soln. of the precipitate in aq. ammonia deposits crystals of the salt. It explodes when heated or struck. It is insoluble in water, and soluble in dil. acids,... 

Copper forms several azides including cuprous CUN3, cupric Cu(N3)2, and a few basic azides. The only copper azide that used to have at least some practical application was cupric azide. Even though the practical application is rather limited, it is important to understand the formation of various copper azides because their formation represents significant risk for munitions containing lead azide. 

Cupric azide Cu(N3)2 is not reported to be light sensitive [15]. It is slightly soluble in water, insoluble in most common solvents except those that form complex compounds [5,6, 15]. It undergoes hydrolysis in boiling water transforming to CuO [6, 102]. Cupric azide Cu(N3)2 is decomposed by mineral acids liberating HN3 [46]. Cu(N3)2 is slowly converted to basic cupric azide in the presence of water or after a... 

Cupric azide Cu(N3)2 forms several basic salts that are described in Table 4.8 [15]. Basic cupric azides are insoluble in water and undergo hydrolysis above 80 °C. They are soluble in acids and bases [5, 15],... 

The basic cupric azides form in principle by partial hydrolysis of cupric azide or by partial reaction of azoimide with Cu(OH)2 [15],... 

Table 4.9 Sensitivity of normal and basic cupric azide to impact in comparison with lead azide and mercury fulminate...

The sensitivity of normal and basic cupric azides to impact varies significantly. The impact sensitivity is represented in Table 4.9 showing that cuprous and cupric azides are more sensitive than LA. Monobasic cupric azide is reported to be more sensitive than LA according to Kabik and Urman [49] and Lamnevik [107] while Fedoroff s encyclopedia reports its sensitivity lower than LA [5]. Basic cupric azides with two or more bases are less sensitive to impact than LA [107]. 

Laboratory preparation of basic cupric azides is based on the reaction of a soluble copper salt with sodium azide (or hydrazoic acid) in presence of a hydroxide (sodium, barium). The reactiOTi conditions influence the type of basic cupric azide formed [15, 108]. 

Lamnevik pubhshed details of the preparation of mono, di, and tribasic basic cupric azides. The monobasic salt was prepared by hydrolysis of cupric azide at 50 °C and dibasic cupric azide by hydrolysis of copper diamine azide at 80 °C. Tribasic salts, together with the monobasic form, are prepared by reaction of copper tetramine perchlorate with sodium azide. The type of resulting product depends on the reaction conditions [107]. 

The copper azides— both normal and basic—have a very hmited field of application with the exception of cupric Cu(N3)2 which has been reported as a primary... 

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