40 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 65 



less readily than >CC1 — - ; and this remarkable result is only 



(27 



to be explained by the absence of free magnetons from the molecule 

 of the former, for that oxide must have much the higher electric 

 energy of the two. In the case of the oxyacids of Chlorine, the 

 velocities of decomposition, under equal conditions, are in the 

 following order : 



o- 



H#@>H^ag>H§a# 



and the same is true for their Potassium salts. Also the heat evolu- 

 tion for complete conversion into KC1 + Oxygen is much greater for 

 KCIO3 than for KC10 4 , and very probably is greater still for KC10 2 . 

 (I have left CLO and HOC1 out of account, because they contain the 

 negative bond, thus : 



{aj-o^a)^{c^o^ci) ^ ci -{oj- ci 

 H— 6-{ci)^H-@@ ==± H-(o)-ci-) 



For Bromine and Iodine the relations are less regular : HBr0 4 is 

 not known, and HI0 4 (2H 2 0) is less stable than HI0 3 . In the case 

 of Nitrogen the oxyacids obey the rule, but most of the oxides do not. 

 No other negative elements satisfy the condition of not combining 

 directly with Oxygen. 



As examples of changes of the type B, we have the following that 

 take place on heating : 



4 KC/0 3 -> 3 KC10 4 -hKCl ] groupV II 



3 //C/0 3 ->HClO 4 +H 2 O + 2C/0 2 j & ° up ' 



4iVa 2 5 , 3 -^3Na 2 SO 4 + Na 2 S ( group VI, 



4 H s PO s aq.-^ 3 H 3 P0 4 + PH 3 1 . 



5A/a 3 ^0 3 ^3Na 3 AsO 4 + 3Na 2 O+^j s v ' 



and others that are spontaneous at ordinary temperatures : 



3H 2 M«0 4 aq.^2H 2 MnO 4 + 2H 2 O + Mn0 2 [group VII, 



SHN0 2 aq.->HN0 3 + H 2 + 2NO \ group V, 



2Na 2 Sn0 2 aq.->Na 2 SnO s + 2NaOH + Sn \ group IV. 



(Unsaturated molecules are italicized throughout.) The effect thus 

 seems very general, although it will be recognized that two or three 



