a f y
AFF
C 21 )
From these data therefore the fused muriat of silver is thus composed:
silver
oxygen
. . 18.7 .
» » * •
• • • »
100.000
•3o8 ) nt g.942 $ 81 ‘ 3
Silver .Oxygen
402.984 ). 31.775 \
| 434.759
100.0
534.759
And the oxyd of silver will consist of
. . 92.67 .
• • » •
100.000
- . 7.33 .
• • • «
. . . .
7.925
100.00
107.925
Therefore 100 parts of muriatic acid saturateSo much of this base as contains 31.775 of oxy-gen, and if the rule of equal saturation be just,every base that saturates 100. parts of dry mu-riatic acid will contain 31.775 of oxygen, pro-vided this analysis of muriat of silver be correct.
Another mode of analysing muriat of silveris by means of the sulphuret. Sulphuret ofsilver the author finds to consist of 100 silverto 14.9 sulphur ; sulphuret of lead contains 100lead and 15.42 sulphur; and suboxyd of leadcontains 100 of lead to 7.7 oxygen. Then,applying Richter’s rule, the sulphur saturating100 parts of lead, is to the oxygen saturating100 of lead, in the same proportion as the sul-phur saturating 100 of silver is to the oxygensaturating 100 of silver. This will give 7.44for the oxygen saturating 100 of silver; for
15.42 : 7.7 :: 14.9 : 7.44. If this result betaken in conjunction with the fact that 100. ofsilver produce 132.7 of the muriat of silver,this 132.7 of muriat will consist of 100. ofsilver, and 7.44 of oxygen, leaving 25.26. forthe muriatic acid. This would give as muchas 19.035 per cent, of muriatic acid in muriatof silver, and only 6.925 per cent, of oxygenin the oxyd of silver; and would give only29.455 for the oxygen in the base saturated by100. of dry muriatic acid.
As the latter mode of estimating muriat ofsilver is obviously exposed to many more sourcesof inaccuracy, the former is preferable. Allthings considered, the disagreement betweenthe two is not very great, though sufficient torender it unsafe to take the mean number asthe most accurate. We may therefore for thepresent infer that a: dry saturated muriat (re-taining the old theory of muriatic acid) containsfor every 100 parts of muriatic acid about 31.5of oxygen in the base which saturates the acid.
The author examines the muriats of copper
and lead with this view. The particulars weshall not here give, but the results considerablyconfirm this general law of equal saturationabove mentioned.
On Water of Crystallization and Water ofComposition.
Water according to Berzelius performs thepart of a base when united to an acid, and ofan acid when in union with a base. Someacids cannot exist in a separate state unless'combined with a certain portion of water, whichportion is exactly sufficient to oxydate thatquantity of any metal which will combine withthe acid to form a neutral compound. This isthe case most remarkably with the muriaticacid, and also with the sulphuric, which lastcan never be concentrated singly to a greaterdegree than that at which it retains as muchwater as contains oxygen equal to half the sul-phur in the acid itself, this being the propor-tion required in the bases saturating this acidas has been already fully described. Hencethe impossibility of forming sulphuric acid bythe combustion of sulphur in dry oxygen with-out the presence of water; and hence when thedry sulphats, such as alum, are distilled’ se,.the product is not sulphuric acid, but only itselements sulphureous acid and oxygen. Thesame takes place with the nitric acid, whichcan never be produced by the mere distillationof the dry nitrats that contain no water ofcyrstallization, as these when heated yield-only oxygen and nitrous acid gas till water beadded.
Besides this water of composition there ex-ists (often in the same compounds) another por-tion, which is the miter of crystallization, andthere seems some reason to infer from theauthor’s numerous experiments, that the quan-tity of water of'crystallization is such that its■oxygen is always a multiplication or a division of.