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8315390 
Journal Article 
The differential thermal analysis of perchlorates. VI. Transient perchlorate formation during the pyrolysis of the alkali metal chlorates 
Markowitz, MM; Boryta, DA; Stewart Jr., H 
1964 
1 
Journal of Physical Chemistry
ISSN: 0022-3654 
68 
8 
2282-2289 
English 
The initial chemical changes in the pyrolysis of the five alkali metal (M) chlorates under a slowly rising temperature program involve the reactions: (a) MClO3 → MCl + 1.502, and (b) MClO3 → 0.75MClO4 + 0.25MCl; subsequent phenomena are associated with the decompositions of the more thermally stable perchlorates, (c) MClO4 → MCl + 2O2. The extent of conversion of MClO3 per reaction b increases in the order Li (40%) < Na (67%) < K, Rb, Cs (87%) at the expense of reaction a. The increasing order of thermal stabilities of these metal chlorates follows the decreasing polarizing powers of M+ though the stability differences among KClO3, RbClO3, and CsClO3 are rather small. Each of the MClO3 compounds appears to possess a congruent melting point in contrast to the corresponding MClO4 salts which, except for LiClO4, undergo simultaneous fusion and rapid decomposition. The catalytic effects of MnO2 additions to MClO3 salts result primarily in the acceleration of reaction a. The general trends in thermal stability among compounds of the type MClOx (x = 1, 2, 3, 4) as a function of M and x are discussed briefly.