WAT
WAT
( 480 . )
Oxygen Gas —Atmofpheric Ah'. The prefenceof oxygen in water may be deteftecl,according toSchede, by filling a phial brimfull with it,dropping in a piece of newly cryilallized ful-phat of iron, and corking the bottle dole. In alittle time the fait will be diffolved, and in afew hours an ochcry precipitate will be per-ceived, owing to the abforption of oxygen by.the oxycl of iron of the lalt, which then becomesinfoluble.
(Teft). Lime or ftrontian water—Litmuswhen in excels— ulphuric acid—boiling.
Sulphuretted Hydrogen.
(Tell). Nitric and oxymuriatic acids—Saltsof lead and iilvcr. A few globules of cleanmercury allowed to remain for feveral hours incontact with the water, clofcly corked, willdetect very minute quantities of it by beingblackened at the furface. Silver leaf willanfwer as well.
Sulphureous Acid.
(Teft). Mr. ICirwan gives as the only deci-sive teft of this acid gas being held in folutionin water, that when mixed with a tindlure ofrofes reddened by an acid it renders this tinc-ture colourlefs. I his acid is alfo known bythe fmell. If perfectly pure it ought not toprecipitate muriated barytes nor nitrated mer-cury, but it always does, which perhaps is owingto an infeparable admixture of lulphuric acid.
Mineral Acids uncombined.
(Teft). Reddening litmus after the water hasbeen boiled.
B r acre Acid .
(Teft). Acetite of lead.
Carbonated Alkalies.
(Teft). Turmeric—Rhubarb—Violets. Ifthe change of colour does not take place afterebullition for feveral minutes, it ftiews that thealkali was ammonia.
Ammonia.
('Teft). The prefence of this a'kali is partlydiftinguiflied in the way mentioned above, butmore certainly by boiling a pretty large quan-tity of the water in a retort, carefully colledtingthe firft ounce or two that dutills, and moift-ening with this portion a piece of well-burntlime, by which the ammoniacal fmell will bediftinftly perceived. The object of this diftil-lation is to concentrate in a l'mall compafs allthe ammonia of a larger quantity of liquid,which might be too dilute to indicate this alkaliwithout this method.
Carbonats of Lime and Magnefia.
(Tefts). Precipitated by ebullition, the for-
mer totally, the latter partially. After boiling,the magnefian carbonat remaining is indicatedby muriat of alumine.
The Acia of the Sulphate.
(Tells). Salts of barytes and lead.—All thefulphats are alfo infolublc in alcohol, and pre-cip'itable by it from their watery folutions.
But fulphat of lime exceeds all the others iathe eafe with which it is thus precipitated.
The Acid of the Muri. ts.
(Teft). Salts of Silver.—Alcohol unlefs veryhighly rectified diOolvcs a fmall quantity of mu-riat of foda, and does not precipitate the muriatswith the eale with which it feparates the fu'phats.
Neutral Salts of Potafj as diflingufhed fromthofe of Soda.
(Tells). Tartareous acid—Nitro-muriat ofPlatina—Acetited barytes with the fulphatsand ccetitecl fiber with the muriats.
The Earth of the Calcareous Salts.
(Teft). Oxalic acid or oxalat of ammonia.—•Pure ammonia not precipitating it. Sulphuricacid, or better the alkaline fulphats, alfo decom-pofes the muriat of lime, and the refulting fele-nite is precipitated. This may be haftened byalcohol.
The earth of the Magnefian Salts.
(Tells). Pure ammonia—Lime-water.
The Earth if the Aiumitipus Salts.
( fell). Pure ammonia—Lime-Water.
Silex.
('fell). This is chiefly fufpeCted by its rc-fufing to diffolve in any acid after the water hasbeen once evaporated to drynefs. It may be morecertainly afeertained by melting it before theblow-pipe with three or four parts of dry car-bonat of foda into a clear globule, which thenwill diffolve in water. Some of the waters thatcontain filex will gelatinize when evaporated al-moft to drynefs, after which ihe filex Will notreaiffolve by reltoring the water which has beenloft. This agrees with the known properties offilex in the analylis of minerals.
(Tefts,. Gals—Prufliat of potafh or lime.The carbonat of iron is precipitated totally byboiling.
Salts of Copper.
(Tells). Prufliat of potafh—Ammonia—Me-tallic iron.
Matiganefe.
(Teft). i he brown colour of its oxyd, andits folubility in carbonat of potafh.
Carbonaceous ihatter.
(Teft). Diffolves in concentrated fulphuri#acid, giving it a clear brown colour.