An introduction to practical chemistry : including analysis . tassium, the latter of which,when dissolved in water, andtested with nitrate of silver, givesa precipitate of chloride of silver(AgCl) (429). 195. (C) The salts of ammoniaare all decomposed when gentlyheated in a test-tube1 with a solu-tion of caustic potash or soda, orwith hydrate of lime (CaO,HO).The fixed alkali here combineswith the acid of the ammoniacalsalt, on account of its superioraffinity, and sets free the ammonia. NH40,S03+JSrO=KO)S03+NH3+ presence of the free ammonia in the upper partof the tube may be proved, (a
An introduction to practical chemistry : including analysis . tassium, the latter of which,when dissolved in water, andtested with nitrate of silver, givesa precipitate of chloride of silver(AgCl) (429). 195. (C) The salts of ammoniaare all decomposed when gentlyheated in a test-tube1 with a solu-tion of caustic potash or soda, orwith hydrate of lime (CaO,HO).The fixed alkali here combineswith the acid of the ammoniacalsalt, on account of its superioraffinity, and sets free the ammonia. NH40,S03+JSrO=KO)S03+NH3+ presence of the free ammonia in the upper partof the tube may be proved, (a) By its well-known odor; (b) By its alkaline reaction on turmeric and reddenedlitmus-paper, which should be previously moistened,and then held within the tube, care being taken that itdoes not touch any part of it; and (c) By the production of dense white fumes of muriateof ammonia (OTI4C1), when a rod moistened with dilute 1 When a liquid is to be boiled in a test-tube, the latter may be con-veniently held in a loop of paper or cloth, as shown in Fig. METALS BELONGING TO CLASS II. 93 hydrochloric acid (HCl) is held near the mouth of thetube. 196. Tartaric acid (2 HO, C8Jff4O10) behaves with ammo-nia in the same way as with potash, throwing down acolorless crystalline precipitate of bitartrate of am-monia (]STH4O,HO,C8H4O10), which is, however, rathermore soluble than the bitartrate of potash (186). Summary of Class I. 197. From the experiments now described, it appearsthat the three alkalies may be distinguished from othermetallic oxides by their producing no precipitate witheither hydrosulphric acid, hydrosulphate of ammonia,or an alkaline carbonate; one or more of which causes,as we shall presently see, a precipitate with all otherbases. Hence, if we have a solution which we knowto contain some inorganic saline matter, and we find noprecipitate produced in it on the application of thosetests, we conclude that the base of the salt is eitherpotash, soda, or ammonia. For
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectchemistry, bookyear18
