Lead chlorite, decomposition

Many of the metal chlorites are not particularly stable and will explode or detonate when stmck or heated. These include the salts of Hg", Tl", Pb ", Cu", and Ag". Extremely fast decomposition with high heat evolution has been noted for barium chlorite [14674-74-9] Ba(Cl02)2, at 190°C, silver chlorite [7783-91-7] AgC102, at 120°C, and lead chlorite [13453-57-17, at 103°C (109). Sodium chlorite can be oxidized by ozone to form chlorine dioxide under acidic conditions (110) ... 

A mixture of 150 parts of oxalic acid, 40 of potassium chlorate, and 20 of water is heated to 60°, and the soln. cone, in vacuo at 50° until it begins to crystallize. The cold liquid i3 then treated with 3 volumes of absolute alcohol, when potassium carbonate is precipitated. Fine deliquescent needles of potassium chlorite can be obtained by fractional crystallization in vacuo. The residue gives a further crop of crystals of the chlorite by treatment with 95 per cent, alcohol. Small yellow crystals of silver or lead chlorites can be obtained by double decomposition. 

Barium and lead chlorites explode on rapid heating at about 460 K and 385 K, respectively. The decompositions of NaQOj (above 413 K) and of AgCCO (above 358 K) are first-order reactions and the values of are 227 and 109 kJ mol, respectively. The major products of AgCCOj decomposition above 373 K are Ag, AgjO and QO. The thermal stabilities of these four chlorites decrease [27,28] in the same sequence (Na, Ba, Ag, Pb) as the ionic character of these solids, covalent character is associated with greater reactivity. 

Evaporation occurs to some extent from any liquid surface. Moreover, all evaporation processes are endothermic. In common with the silver chlorite decomposition mentioned above, this process leads to a significant volume... 

The chlorates, like the nitrates, are all readily soluble in water lead and silver chlorites, like the corresponding nitrites, are sparingly soluble salts and lead perchlorate is the only salt which does not easily dissolve. As already mentioned, chloric acid is readily decomposed when its aqueous solution is warmed chlorous acid is still less stable but perchloric acid, which may be prepared by distilling together potassium perchlorate with concentrated sulphuric acid, is relatively stable, seeing that it can be distilled without decomposition. It is an oily liquid, with acid taste it is apt to explode when brought into contact... 

Evaporation of sodium chlorite solutions may lead to loss of chlorite through decomposition and this has been examined . Two parallel reactions... 

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