332 



EXPERIMENTS ON THE METALS FROM THE TIXED ALKALlf. 



Action of po- 

 tassium on tel- 

 lurium. 



water entirely dissolved, making a bright purple tincture. 

 A compound of It immediately occurred to me, that the whole of the hidro- 



tellurium, hi- i • L • ,ji , .... 



drogen, oxigcn,S en ? which in common cases would hare been furnished 

 and potassium, from the decomposition of the water, had in this instance 

 ? r0 uc combined with the tellurium ; and that the telluretted hidro- 



gen, (if the name may be used,) had formed with the 

 oxidated potassium, i. e. the potash, a peculiar compound, 

 soluble in water: and this I found to be the case; for, on 

 pouring a little dilated muriatic acid into the mixture, it 

 effervesced violently, and gave a smell very like that of 

 sulphuretted hidrogen ; metallic tellurium was formed where 

 it came into contact with the air, and muriate of potash w r as 

 found dissolved in the mixture. 



It seemed evident from this fact, that, in the action of 

 tellurium negatively electrified upon potash, potassium was 

 produced, as in all other cases, and that it combined with 

 the tellurium, and formed a peculiar alloy; and this opi- 

 nion was farther confirmed by the immediate action of 

 potassium upon tellurium. When these metals were gently 

 heated in a retort of green glass, filled with hidrogen gas, 

 they combined with great energy, producing most vivid 

 heat and light, and they composed an alloy of a dark cop- 

 per hue, brittle, infusible at a heat below redness, and 

 possessing a crystalline fracture. When the tellurium was 

 in excess in this mixture, or even nearly equal to the potas- 

 sium in quantity, no hidrogen was evolved by the action 

 of the alloy upon water; but the compound of telluretted 

 hidrogen and potash was formed, which remained dis- 

 solved in the fluid, and which was easily decomposed by 

 an acid. 



The very intense affinity of potassium and tellurium for 

 each otheF induced me to conceive, that the decomposition 

 vived together of potash might be easily ejected, by acting on the oxide 

 by charcoal. f tellurium and potash at the same time by heated char- 

 coal ; and I soon proved, that this was the case. About 

 100 grains of oxide of tellurium, and 20 of potash, were 

 mixed with 12 grains of well burnt charcoal in powder, 

 and heated in a green glass retort; before the retort became 

 red there was a violent action ; much carbonic acid was given 



off, 



Oxides of po- 

 tassium and 

 tellurium re 



