Decomposition reactions compositions

Some of the composition adjustments in the Alnicos result in a high Curie temperature so that the decomposition reaction can take place relatively rapidly below This is particularly tme for Co, which is 24 wt % or greater for the anisotropic magnets. Another important consideration is the suppression of nonmagnetic fee y-phase which may appear at 1000—1100°C in this regard, the amount of Al, which is a y-suppressor, is critical. The formation of y is pronounced if the Al content falls much below 7—8 wt %. 

When AN particles are mixed with GAP, AN-GAP composite propellants are formulated. The specific impulse is increased by approximately 10 s by replacing PB or PU binder with GAP, as shown in Fig. 4.16. The burning rate is also increased due to the exothermic decomposition of GAP. Since GAP burns by itself, the burning of the AN particles is supported by the exothermic decomposition reaction of the GAP at the burning surface of the propellant. As shown in Fig. 7.61, the burning rate is drastically decreased by the addition of AN particles. When is in-... 

In aqueous solutions, calcium chloride undergoes double decomposition reactions with a number of soluble salts of other metals to form precipitates of insoluble calcium salts. For example, mixing solutions of calcium chloride with sodium carbonate, sodium tungstate and sodium molybdate solutions precipitates the carbonates, tungstates, and molybdates of calcium, respectively. Similar precipitation reactions occur with carboxylic acids or their soluble salt solutions. CaCb forms calcium sulfide when H2S is passed through its solution. Reaction with sodium borohydride produces calcium borohydride, Ca(BH4)2. It forms several complexes with ammonia. The products may have compositions CaCl2 2NH3, CaCb dNHs, and CaCb SNHs. 

The decomposition reaction of potassium chlorate is rare among the common oxidizers because it is exothermic, with a heat of reaction value of approximately -10.5 kcal/mole [ 2]. While most other oxidizers require a net heat input for their decomposition, potassium chlorate dissociates into KCl and O2 with the liberation of heat. This heat output can lead to rate acceleration, and allows the ignition of potassium chlorate-containing compositions with a minimum of external energy input (ignition stimulus). 

Since the nitrite of a given metal is generally much less stable than the nitrate, the former can appear only as an unstable intermediate in the decomposition of the nitrate. This is particularly true for covalent nitrates. In the case of ionic nitrates, however, both salts may be more or less equally unstable over some temperature range, so that the decomposition reactions can become quite complex. This is particularly so since the salts may be oxidized or reduced by the gaseous decomposition products. For example, N02 produced by the decomposition of the nitrate may oxidize the nitrite ion also formed back to the nitrate. Since the experimental arrangement usually determines the gas-phase composition, reports by different authors frequently conflict. In such cases the common features have been emphasized in this chapter. A consequence of the complexity of most nitrate decompositions is that kinetic studies have usually been restricted to identifying the reactions. Even when rate constants and activation energies are reported it is frequently not clear with which particular reactions they are identified. 

The effect of gas composition and pressure on the temperature range over which the decomposition reaction occurs can be seen by comparing the above results with a TGA study under vacuum.19 The first stage of the decomposition, corresponding to... 

The composition of the fumes produced by the detonation of an explosive can be found by calculation (-> Thermodynamic Calculation of Decomposition Reactions) or by detonating a cartridge of the explosive in question in a closed vessel (-> Bichel Bomb) followed by gas analysis of the fumes. 

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