376 



Dr. E. J. Mills on the Action of Heat 



Action of Heat on Potassic Chlorate. 

 The products of this action are potassic chloride, oxygen, 

 and perchlorate. All known relations among these products 

 may be expressed by the cumulative equation 



2nKC10 3 -(n-2)O s = (n + l)KC10 4 +(n-l)K01. 

 In order to compare theory with experiment, I have selected 

 the quotient of the percentage of chloride produced by that 

 of the oxygen formed as the specific measure of the change .; 

 the percentage being calculated on the weight of chlorate 

 taken for trial. If this quantity be called r, the equation 

 alleges that 



2 n-1 



rx 



KCl~rc-2 ; 



or 



■42867r= 



n — 1 



n — 2 



It will be seen from the following Table that this is the case ; 

 a rational value of n always corresponding to the specific 

 measure r. No attention has been paid to instances in which 

 perchlorate is known to have been decomposed. When n= oc, 

 the equation becomes 



2K010 3 - 2 = KC10 4 + KC1. 



Table I. 



No. of 

 exp. 



Oxygen, 

 per cent. 



Chloride, 

 per cent. 



r. 



n. 



Authority. 



1. 



1-66 



5-26 



3-1687 



4-7910 



Teed. 



2. 



3-49 



10-86 



3-1117 



4-9949 



»> 



3. 



6-00 



18-25 



3-0417 



5-2906 



„ 



4. 



2-66 



* 9-4916 



3-5684 



3-8879 



Frankland and Dingwall. 



5. 



5-19 



*18-566 



3-5774 



3-8744 



„ 



6. 



647 



#21-609 



3-3399 



4-3164 



» 



7. 



6-89 



#21-533 



3-1253 



4-9438 



>> 



8. 



6-78 



#20-147 



2-9715 



5-6523 



„ 



9. 



3-6 1 



11-58 



3-2167 



4-6392 



Teed. 



10. 



1-27 



4-73 



3-7244 



3-6764 



»> 



11.. 



1-61 



600 



3-7267 



3-6736 



)> 



12. 



1-60 



6-14 



3-8375 



3-5502 



» 



13. 



1-47 



4-84 



3-2925 



4-4307 



»> 



14. 



0-80 



2-18 



2-7250 



7-9488 



>> 



It is remarkable that the value of n should, amongst so 

 many experiments, prove to be so very restricted in its range. 

 There seems to be some tendency for r to be preferably about 

 equal to ri. The exact fulfilment of this condition requires 



* ^Recalculations. 



