Heavy metals saturated aqueous solutions

Table 20.18. Saturated aqueous solutions made from inorganic salts of heavy metals "...

Not yet understood is the phenomenon of spontaneous explosion in saturated azide solutions, which has been observed during crystallization of cadmium [216], copper(II) [224], mercury(II) [224], and lead [176,223,224, 280,286] azides, in both aqueous and gel media [281]. Explosions occurred at elevated as well as room temperatures [281,282]. Research so far has aimed at avoiding [282,283] or producing [284,285] the effect. In lieu of more solid advice, it may be said that the reported explosions evidently occurred in highly complexed solutions, usually containing the heavy-metal ions in excess. 

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