SOL
SPE
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SOLUTION. Auflofung. Germ.
Solution is the perfect chemical union of afolid or fluid with any other fluid, in which thecompound remains in a liquid ftate, and per-fectly homogenous in all its parts. It generallyis applied to the melting down of a folid in afluid (fait in water for example) but appliesWith equal propriety to the chemical union oftwo diflimilar fluids, as where an effential oil isdiflolved in alcohol.
Solution is one of the great operations inchemiftry, and alrnoft every fubftance in natureis capable of it. The antient idea of folutiondoes not imply chemical affinity, and the fub-ftance diflolved was fuppofed to be as it werepaffive in the operation,, fo that in this point ofview, folution was little' elfe than tranfparentdijf'ufson. But more accurate ideas of chemicalaction have Ihewn that folution takes placefrom true chemical affinity operating betweenthe fplvent and- the folvend , in which each fub-ftance equally participates. For a folid to bediflolved in a fluid it is neceflary that the forceof affinity between the two fhould be fufficientto overcome the' force of cohefion between theparticles of the folid, and hence it is that heatfo much affifts folution by IdTening the forceof cohefion between all particles of matter.
It generally happens in all cafes of folution ata common temperature that the mixture in thea cl of folution becomes either warmer or colderthan the ingredients were before mixture. Thisarifes from an evolution or abforption of freecaloric, owing to the mixture having a lefs ora greater capacity for caloric than the mean ca-pacity of the two fubftances taken feparately.This has been more fully explained under thearticle Caloric .
It happens alfo in by far the greater numberof cafes of folution that the mixture has agreater fpecific gravity than the mean gravityof the ingredients, relatively, to their refpe&ivequantities. Hence they occupy lefs fpace thanbefore, as may readily be feen by putting intoa bottle any loluble fait (fulphat ®f foda forexample) and.filling it brim-full of water, andalter the folution. is effe&ed, .the liquor willhave funk a certain way below the firft levelwithout any lofs of the ingredients.
The whole-fubjett of folution is intimatelyconnected with that of chemical affinity towhich we fiiali refer.the reader.
SOOT.
Chimney foot is a compound of black car-bonaceous matter with a coiffiderabie quantity
of carbonated ammonia and probably. fome -other ammoniacal falts, and hence it gives aftrong pungent lmell of this alkali when rubbedwith quicklime. Carbonated ammonia is ex-tracted from it in the large way in feveralmanufactories of this fait.
SORREL, Salt of, is the native fuper-oxalatof potaffi contained in the juice of this plant.See Oxai.ic Acid.
The fubftance originally called by this name,,is the white of oxyd or magiftery of bifmuth,.the name is often however applied to walked,chalk or whiting.
SPAR. Spath. Germ.
The term lpar, in its moft comprehenfivefenfe appears to include alrnoft all the earthycryftallized minerals that are met with in me-tallic veins ; but by mineralogifts it is appliedto thofe minerals whether earthy or metallic,which are cryftallized and have a vifible foliated-texture. Thus we fay calcareous fpar, fluorfpar, heavy fpar, felfpar,. lead fpar, fpathofeiron, &c. but not quartz fpar. It is not how-ever every foliated cryftal which is called afpar, for neither mica nor hornblende bearthis appellation. The adjective fpathofe or -fparry, means compofed of crystalline plates,in oppofition to foliated or flaty, which onlyimply compofed of plates, without any refer-ence to cryftallization.
SPARGELSTEIN. See Afatit.
SPECULUM METAL. See Copfer, al-loys of..
SPELTER.
Is the ufual commercial name for Zinc .
SPERMACETI. Blanc de Baleine. Fr...Wallrath. Germ.
This peculiar oily fubftance is found abun-dantly in the cranium of the cachalot or fper-maceti whale (Phyfeter macrocephalus, Linn.)and in fome other fpecies of the fame genus:but though contained in the cavities of. thelcull it appears to be entirely-difTrem from theproper brain of the a’nimal. When firft ex-tracted it is mixed with a confiderable quantityof oil, which is feparated by putting the matsinto a woollen- bag and prefling it, by whichthe treated: part of the oil runs cut, and thenwaffiintt the refidue with a warm weak alkalineley, which dhTolves and converts into foap theremainder of the oil, leaving behind the fperma-ceti untouched ; this latter after Icing repeat-edly wafhed with foft water, is melted by avery gentle heat, the impurities partly float or.