CHEMISTRY. 



103 



Elements stituents combine. The following Table exhibits the 

 general result of these experiments. The numbers re- 

 ^ 15try ' present the weight of the different acids and bases 

 which neutralize each other respectively. 



Aciils. 



Sulphurous 

 Oxalic 

 Nitric 

 Sulphuric . 

 Phosphoric 

 Muriatic . 

 Carbonic . 

 Phosphorous 



Ttble of 

 chemical 

 Deeompo- 



54- 



39.5 



33.3 



37.5 



23 



18 



20.5 



32 



Bases. 

 Barytes 

 Stroniian 

 Potash 

 Soda . 

 Lime . 

 Magnesia 

 Ammonia 



72.8 

 4-6 



42.11 

 29.75 

 27.2 

 17.76 

 9 



Suppose we wish to form, sulphate of barytes from 

 the above Table, it appears that we must unite together 

 ^7.5 parts by weight of sulphuric acid, and 72.8 parts of 

 barytes. 



From various experiments hitherto made, it appears 

 that the supersalts contain twice as much acid, and the 

 subsalts twice as much base, as the neutral salts. Suppose 

 that a given quantity of sulphate of potash is composed 

 of 100 potash, united with x of sulphuric acid, then su- 

 persulphate of potash is composed of 100 potash, united 

 with 2j: sulphuric acid. The triple salts appear to con- 

 sist of two different salts united together. Thus alum 

 may be considered as a compound of sulphate of potash 

 and sulphate of alumina. 



According to the old doctrine of affinity delivered by 

 Bergman, all bodies capable of combining have an affini- 

 ty for each other. This affinity is a c-.-nstant force, 

 which may be represented by numbers. Affinity is e/ec- 

 live ; that \ to say, if a has a stronger affinity for m than 

 It has, and if m be combined with b, forming a compound 

 which we may represent by mb ; a, upon being mixed 

 with this compound, has the property of separating b 

 completely from m, and taking its place, so as to form a 

 compound ma, while b is entirely disengaged. This 

 doctrine has been lately called in question by Bcrthollet. 

 According to Berthollet, affinity is not elective, and never 

 occasions decomposition, but only combination. The 

 decompositions which take place are owing to other 

 causes, such as insolubility, elasticity, Ac. though this new 

 opinion (if accurate) renders Bergman's tables of decom- 

 position of little comparative value ; yet, as it is, seems 

 inconsistent with facts, and as his tables are in some cases 

 useful, and are often referred to, it has been thought 

 worth while to subjoin them here. 



Table of Chemical Decompositions. 



Phosphoric 



Sulphuric 



Fluoric 



Arsenic 



Sarlactic 



Succinic 



Nitric 



Muriatic 



Tarlaric 



Citric 



Malic 



Benzoic 



Acetic 



Boracic 



ulphtirous 

 Sitrous 



'arlxmic 

 Prussic 



Elements 



of 

 Chemistrv. 



