COMBINATIONS OF OXIMURIATIC GAS AND" OXIGEK. jQf 



I shall now resume the detail of the experiments that I Potassium 



, , . ^. x' £• • ' 1.' burned in oxV» 



have made, on the relative attractions ot oximuriatic gas 



and 



In my first experiments for producing potassium and sodium, I used In the produc* 



a weak powtr: and in these instauces, procnring the metals in rery *'°" °* potas- 



,, . . , , . , „. ,,,, - „ sium inquan- 



nuall quantities only, I perceived mo effervescence. When from five ^- j^j^rogea 



hundred to one thousand plates art used for producing potassium, evidentlr 



there is a violent efftivescence, and a production of hidrogen, and evolved, 



sometim* s of potassuretted hidrogen, connected with the formation of 



the metal. 



Potassium, broxight into contact with redhot hydrat of pot?ish, dis- ^g jt jg jj, other 

 engages abundance of hidrogen, and the whole is converted iuio diffi- experiments, 

 cultly fusible potash. 



327 ti;rains of hydrat of potash, that had been ignited, were made 

 to act in a gunbarrel on 745 grains of iron turnings heated to white- 

 ness. Some hidrogen was lost, and some hydrat of potash remained 

 undecompounded, yet 225 cubical inches of inflammable gas were col- 

 lected, and 50 grains of potassium, and a large quantity of an alloy 

 of potjjiSsium and iron foiraed ; so that it is scarcely possible to doubt, 

 that all the hidrogen produced from the decomposed hydrat of potash 

 was liberated. 



Mr. Dalton conceives, that- there is an analogy between potassium Observations 

 and sodium, and the compounds of hidrogen with sulphur, phospho- on some opi 

 rus, and arsenic ; bat 1 am at a loss to trace any similarity between nions of Mr. 

 sulphuretted hidrogen, which is a gaseous body, soluble in water, and 

 having acid properties, and a highly inflammable solid metal, which 

 produces alkali by combustion. Potassium might as well be compared 

 to carbonic acid. Mr. Dalton considers the volatility of potassium 

 and sodium as favouring the idea of their containing hidrogen; but 

 they are less volatile than antimony, arsenic, and tellurium, and much 

 Jess volatile than n^ercnry. He n^eutjons their low specific gravity as 

 a circumstance favourable to this idea. I haye on ^ former occasion 

 examined this argument, first brought forward by Mr. I^itter ; but it 

 may not be amiss to add, that, if potassium is a compound of hidre. 

 gen and potash, hydrat of potash must contain an equal quantity of 

 hidrogen, with the addition of a light gaseous element, oxigen, which 

 might be expected to diminish rather than to increase the specific 

 gravity of the compound. ]\Ir. Dalton states, p 488, that potassium 

 forms dry hydrat of potash, by decomposing nitrous gas and nitrous 

 oxide; this is not the case: and he does not refer to experiment. I 

 find by some very careful trials, that potassium attracts the oxigea 

 and some of the nitrogen from these bodies, and forms a fusible coro- 

 pvund which may be decomposed, giving off nitrogen and its excesw 

 of oxigen, by a red heat, and which becomes potash, and not i^ry |iy^ 

 dr»t of potash. ; ; i ^ 



Measre^ 



