PROPORTIONS DETERMINATE. 



179 



Propor- that the quantity of that common element contained 

 tioni, by |j le one j s an integer multiple of the quantity con- 

 tained by the other; or when the number of compound 

 bodies is greater, &c. &c. It is conformable to this 

 law, that in fossil combinations of the dilferent metal- 

 lic sulphurets, the sulphur of the one is always a mul- 

 tiple of that of the other. It happens sometimes that 

 compound bodie., of which the electro-positive element 

 is common, may enter into combin ition. Those com- 

 binations have been little examined ; but it appears 

 that the electro-negative elements divide the elcrtro- 

 }>o>itive one among them, in some multiple proportion. 

 Such, for example, are mispickel, compounded of sul- 

 phurct and ar.-eniate of iron, in which the iron is 

 equally divided between the sulphur and the arsenic ; 

 the double salt having for its base the oxide of lead, 

 combined with nitric acid and phosphoric acid ; in 

 which the Litter occupies twice as much of the base as 

 the former. 



From these two laws are deduced all the phenome- 

 na of chemical proportions. Sulphuric acid, for ex- 

 ample, contains three times as much oxygen as the base 

 by which it is neutralized. Hence when any sulphate 

 of a metallic oxide is decomposed by another metal, the 

 latter precipitates the dissolved metal under a metallic 

 form, without altering its neutrality, because the sul- 

 phuric acid must, as formerly, contain three times 

 the oxygen of the metal last dissolved, and therefore 

 the oxygen remains without alteration, nothing but the 

 metallic radical being changed. Now, since the rela- 

 tion between the oxygen of the base and that of the 

 acid is invariable, with regard to all neutral salts of the 

 same acid, the constant ratio in the capacity of bases 

 to saturate acids, observed and proved by Wenzel and 

 Richter, follows as a necessary consequence from this 

 tact ; ami such neutral salts as mutually decompose 

 each other must, therefore, still maintain their neutra- 

 lity. If, on the contrary, which rarely happens, the 

 ratio between the oxygen of the base and that of the 

 acid is different for different bases, two neutral salts 

 may happen from this circumstance to decompose each 

 other, and at the same time lose their neutrality (as 

 the muriate of glucina and the fluate of soda, the car- 

 bonate of potass and muriate of lime, sulphate of am- 

 monia and muriate of barytes) without however being 

 in opposition to the above laws; for in such cases the 

 oxygen of the base becomes a submultiple of that of 

 the acid by a different number. 



Yet the two principal rules just mentioned 'are not 

 absolutely without exception. Sulphur, in particular, 

 forms an exception to the first. In the case of this 

 substance we are acquainted with no more than two 

 degrees of oxidation, the highest of which, sulphuric 

 acid, contains but 1^ time as much oxygen to the 

 same quantity of sulphur, as the lower degree, sulphu- 

 rous acid. The same is the fact with regard to iron. 

 Antimony also has several degrees of oxidation, the se- 

 cond of which contains but l time as much oxygen 

 as the first. It is quite possible, however, that these 

 exceptions may be apparent only. They would in fact 

 be so, should it be found that there are other lower 

 degrees of oxidation not yet discovered, or not capable 

 of existing in the isolated state. It is thus we have 

 reason to consider sujphur combined with oxymuriatic 

 gas as being in the state of an oxide, the oxygen of 

 which, found by calculation, is exactly one-half of that 

 contained in sulphurous acid. If this is really the case, 

 the degrees in which sulphur unites with oxygen are 

 to each other as 1,2, and 3. In like manner, the protox- 



ide of iron may contain two times, and the protox- 

 ide of antimony three times, as much oxygen as exist* 

 in some first degree of oxidation not yet discovered. 



The exceptions to the second rule are fewer in num- 

 ber, but at the same time more striking and worthy 

 of attention. In the greater part of thote combinations 

 among oxidized bodies hitherto analyzed, none but the 

 oxides ul' two individual radicals have been found to 

 contradict this rule. The oxides in question are those 

 which have nitrogen and phosphorus as radicals, 

 trogen and phosphorus combine with oxygen in 

 ent degrees, the last two of which are acids. In t!c 

 case of other radicals giving two acid*, the ratio of the 

 oxygen contained by the acid in its higher state of 

 oxidation, to that contained by the acid in its lower 

 st.ue of oxidation, is as 2 to 3 ; in the case of nitrogen and 

 phosphorus as 3 to 5. M. Berzelius attempts to ex- 

 plain these deviations in the following manner. The 

 composition of neutral nitrates is conformable to the 

 rule so far that the acid contains five times as mucii 

 oxygen as die base ; but the composition of subni- 

 trates, three ditferent degrees of which he has exa- 

 mined, varies from it ; the oxygen of the first subui- 

 trate being a multiple by 2$ of that contained by the 

 base ; in the second, a multiple by 1 ; in the List, a 

 multiple by ['.. Comparing these fractions witli 

 each other, and with the numerous analytical result-, 

 so exactly conformed to the rule, it would seem that 

 some unknown circumstance has in this case produced 

 an exception, not real but apparent. If the supposi- 

 tion so long entertained, that nitrogen is not a simple 

 body, be in truth well founded, these aberrations are 

 capable of being easily and fully explained. One vo- 

 lume of nitrogen gas combines, in its different oxides, 

 with 4, 1, l^, and 2^ volumes of oxygen gas; from 

 which it follows that if nitrogen really contains oxy- 

 gen, it can only contain the half of its volume ; so 

 that nitrogen would, on this supposition, be composed 

 of one volume of a radical, unknown in its isolated 

 state, and one volume of oxygen. Upon this hypothe- 

 sis, the different degrees of oxidation which a volume 

 of this radical admits, are produced by adding a vo- 

 lume of oxygen gas according to the following series : 

 1, 2, 3, 4, and 6; a series far more natural than the 

 first. Now, as nitric acid contains six volumes of 

 oxygen, the nitrates and subnitrates mentioned above 

 no longer form exceptions to the rule ; for in neutral 

 nitrates the oxygen of the acid is six times that or the 

 base; in the first two subnitrates, three and t.vo times 

 that of the base ; and finally, in the last subnit- 

 rate, the oxygen of the acid is equal in quantity to 

 that of the base. This mode of viewing the compo- 

 sition of nitric acid becomes still more plausible. 

 when the composition of ammonia is examined. This 

 alkali has the closest analogy with the fixed alka- 

 lies, in all its properties, even in the method by 

 which it is reduced to a metallic body, in the cir- 

 cuit of the electric pile. Its composition must, 

 therefore, in like manner, be analogous to theirs ; and 

 if the former bear to the latter such a relation, for 

 example, as the composition of acetic bears to the com- 

 position of sulphuric acid, we are naturally led to sup- 

 pose in ammonia the existence of a quantity of i 

 capable of being calculated from the quantities ot am- 

 monia necessary for di.-placing, from its combination 

 with an acid, another oxide, the quantity of whose 

 oxygen is known. In neutral carbonates, proportional 

 to the neutral carbonate of ammonia, the carbonic; acid 

 contains four times the oxygen of the base ; while thL> 



