Azides of Group VIIA

Of all known normal azides including HN3, fluorine azide appears to be the most sensitive. The greenish-yellow gas was obtained in a nitrogen or argon environment at low temperatures. Slow mixing of diluted (1 200) fluorine and HN3 yielded the azide, apparently according to [334]  

Chlorine azide tends to explode spontaneously even at reduced pressure. Mixtures with inert gases appear to be more stable but are still sensitive to mechanical or thermal shock. Solutions in organic solvents have shelf lives of several days at room temperature and in the dark [335,336]. 

Chlorine azide gas is prepared [336,340] in acid media according to  

Acetic and boric acids are useful for the process as they react without gaseous by-products. Mineral acids liberate hydrazoic acid and thus contaminate the 

QN3 MP,-45°C BP, 15°C Room temperature Spontaneous explosions at room temperature 335,336 

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