330 



EXPERIMENTS ON THE METALS FROM THE FIXED ALKALIS. 



Mr. Ritter's 

 hypothesis 



jrcfuted. 



His observa- 

 tions on the ac- 

 tion of tellu- 

 rium upon 

 water. 



were made to act upon water; they decomposed it with the 

 phenomena, which I have described in the Bakerian lec- 

 ture for 1807*. Nearly 6 cubical inches of hidrogenwere 

 produced. No charcoal separated; no carbonic acid was 

 evolved, or found dissolved in the water. Whether the 

 metals of potash or soda were formed by electricity, or by 

 the action of ignited iron on the alkalis, the results were 

 the same. When charcoal is used in experiments on potas- 

 sium or sodium, they usually contain a portion of it in 

 combination, and it appears from Mr. Curaudau's method 

 of decomposing the alkalis, that his metals must have been 

 carburets not of potash and soda, but of potassium and 

 sodium. 



Mr. Hitter's argument in favour of potassium and so- 

 dium being compounds of hidrogen is their extreme light- 

 ness. This argument I had in some measure anticipated, 

 in my paper on the decomposition of the earths ; no one 

 is more easily answered. Sodium absorbs much more 

 oxigen than potassium, and, on the hypothesis of hidroge- 

 nation, must contain much more hidrogen ; yet, though 

 soda is said to be lighter than potash in the proportion of 

 13 to 17 nearly +, sodium is heavier than potassium in the 

 proportion of 9 to 7 at least. 



On the theory which I have adopted, this circumstance is 

 what ought to be expected. Potassium has a much stronger 

 affinity for oxigen than sodium, and must condense it much 

 more, and the resulting higher specific gravity of the com. 

 bination is a necessary consequence. 



Mr. Ritter has stated, that, of all the metallic substanceB 

 he tried for producing potassium by negative voltaic electri- 

 city, tellurium was the only one, by which he could not 

 procure it. And he states the very curious fact, that, when 

 a circuit of electricity is completed in water, by means of 

 two surfaces of tellurium, oxigen is given off at the positive 

 surface; no hidrogen at the negative surface, but a brown 

 powder, which he regards as a hydruret of tellurium, is 

 formed and separates from it; and he conceives, that the 

 reason why tellurium prevents the metallization of potash is, 



* Journal, vol. xx, p. 307. 



f Hassenfratz, Annal. <Je Chem, lorn, xxviii, p. 11. 



that 



