36i 



ON THE ALKALINE METALLOIDf« 



have been 

 neutralized. 



Inf«ffenceau 



product of the combustion of potassium. Hence the agree- 

 ment in the conclusion, that the alkaline strength of the 

 former is superior to that of the alkali in its real state. 

 CalcMlation of To perceire more clearly to what conclusion this result, 

 icid^that should ^"PP°^^"S ^^ *^ ^® correctly established, leads, it may bo 

 calculated what quantity of acid the quantity of real alkali 

 from 4*3 of potassium ought to neutralize. Five grains of 

 ignited potash, containing 14 per cent of water, neutralize 

 139 grains; five grains of real potash, free from water, 

 ought, according to this, to neutralize 162 grains; which 

 is the quantity of course which the 4*3 of potassium ought 

 to hare neutralized, on the supposition that in combining 

 with oxigen it forms the real alkali. 



Now although the alkali produced from the oxigenation 

 of potassium is thus inferior to real potash in neutralizing 

 power, a result which so far supports the speculation I 

 have advanced, yet it appears to be superior considerably 

 to the ignited potash; and this may be supposed therefore 

 to invalidate the first series of experiments, in which the 

 alkali formed by the combustion of potassium was found 

 little superior to ignited potash. To admit of this latter 

 conclusion, however, it must be supposed, that the 

 proportions in which potassium and oxigen combine 

 to form pure potash are accurately estimated ; and th^ 

 can scarcely be considered as determined with perfect 

 certainty. No experiment is more exposed to sources of 

 errour, both from the different degrees of oxidation of which 

 potassium appears to be susceptible, and the action which 

 it exerts during its combustion on the substance with which 

 it is in contact. These become too, of much greater impor- 

 portance in the experiment, and even the accuracy of the 

 estimate, independent of them, becomes more doubtful, 

 from the sraallness of the quantities which have hitherto 

 been operated on. If from any of these circumstances the 

 proportion of oxigen has been underrated, even to a small 

 extent, the difference between the result of the above expe- 

 riment, and of that in which the alkaline strength of th« 

 product of the combustion of potassium was directly ascer- 

 tained, will be accounted for. 



Another 



Objections to 

 these. 



