[chadsey] decomposition OF POTASSIUM CHLORATE 



25 



expressed as percentages. The value for each, as demanded by the 

 iforegoing equations are given, and below are the calculated values for 

 a number of decompositions in which none of the perchlorate had 

 decomposed. The values are given for the oxygen in a number of 

 cases, the first value being calculated from the actual loss of weight 

 of the bulbs, and the second (in brackets), from the total oxygen from 

 decomposed chlorate less the oxygen required for the perchlorate 

 formed. In every case, indeed, the larger value for the oxygen gives 

 a number in Table 2 nearer that required by the equations, and there 

 is in this an additional reason for assuming that a part of the oxygen 

 is absorbed by the heated glass. 



Table II. 



The majority of results evidently approximate most closely to the 

 8 KCIO^ equaftion, one very close'ly to that beginning with 22 KCIO^, 

 while two of them do not correspond with any of the three. 



The maximum amount of perchlorate should therefore be obtained 

 by interrupting the reaction when, from each 100 grams of chlorate 

 heated, about 4-5 litres of oxygen have been evolved. This relation 

 appears to be independent of the temperature since this affects only 

 the rate of the reaction. Decompositions which have passed the point 

 where the perchlorate begins to break down, cannot be expressed by 

 any definite equation. 



