386 Intelligence and Miscellaneous Articles. 



organic bodies yields oxide of carbon : this happened especially 

 during the decomposition of oxalic acid by M. Gay-Lussac. M. 

 Pelouze states, that with proper precautions, and especially by keep- 

 ing a proper temperature, this apparent anomaly may be avoided, and 

 the law above stated will hold good. 



M. Despretz remarks, that the two compounds obtained with the 

 pyrogenous acids are the most stable yielded by the elements pre- 

 sent ; and this circumstance would lead ci priori to the law indi- 

 cated. — Journal cle Chimie Medicate, Feb. 181^4. 



ON HYPERIODIC ACID AND HYPERIODATES. 



MM. Amtnermuller and Magnus remark, that considering the 

 strong resemblance which exists between chlorine and iodine, it 

 appears singular that analogous compounds of these with oxygen 

 have not yet been discovered, especially as the affinity of iodine for 

 oxygen appears to be stronger than that of chlorine. The method 

 of Serullas for procuring hyperchloric acid does not succeed for 

 procuring hyperiodic acid, for on heating iodate of potash, hyper- 

 iodate cannot be procured. M. Liebig's method of procuring io- 

 date of scda consists in mixing iodine with a large quantity of water, 

 passing excess of chlorine into it, and adding carbonate of soda 

 to the solution. When saturation is effected, a considerable quan- 

 tity of iodine is precipitated : fresh chlorine is passed into the so- 

 lution until all the iodine precipitated is redissolved. The saturation 

 with soda is repeated, iodine again separates, and then chlorine 

 must be added till no more precipitation takes place. The iodate 

 of soda is separated by evaporating the clear solution, and treating 

 it with alcohol. 



During this process a white pulverulent matter, insoluble in water, 

 was obtained, and this, considering the circumstances under 

 which it was formed, appeared to be subhyperiodate of soda ; and 

 it was soon found that it might be procured by adding a solution of 

 soda to one of iodate of soda, and passing chlorine into the mixture. 

 The separation of this salt is accelerated by a gentle heat, and if 

 carbonate be used instead of caustic soda, the mixture must be 

 heated nearly to ebullition, because at common temperatures hy- 

 periodic acid cannot expel the carbonic acid of the carbonate. 



Instead of passing chlorine gas into the solution, a mixture of 

 iodate and chlorate of soda may be heated with chloride of soda, 

 obtained by decomposing chloride of lime with carbonate of soda. 



Having found that the subhyperiodate of soda gave out oxygen 

 when heated, an attempt was made to analyse it; but the diffi- 

 culties were such as rendered it necessary to employ another salt 

 for this purpose, and that of silver seemed preferable. It was pre- 

 pared by dissolving the salt of soda in dilute nitric acid, and precipi- 

 tating with a solution of nitrate of silver. When the acid was slightly 

 in excess, a bright yellow precipitate with a; tint of green was ob- 

 tained, and this was washed with water acidulated with nitric acid. 

 It was then dissolved, with heat, in dilute nitric acid, and then, by 

 crystallization, there were obtained small brilliant crystals of a pale 

 straw colour. When these were treated with hot water they became 



