Bicarbonate of potassa

Properties.—Bicarbonate of potassa, in the crystalline condition, has the form of an oblique rhombic prism, and fa combined with an equivalent of water. Its formula is KO, 2 COE, HO. It is unalterable in the air, but when strongly heated loses half its acid and the whole of the water, reverting to the state of neutral carbonate. When heated in woter, also, it is partially decomposed, and, by long boiling, completely, with production of neutral carbonate. The taste and reaction of bicarbonate of potassa is slightly alkaline. It dissolves to four parte of water at 60 , and in little more than its own weight of this liquid at a boiling heat. In alcohol it is nearly insoluble. It, is occasionally employed in tbs preparation of pure neutral carbonate of potassa. 

Arsenitis Fotasss Liquor (tasteless ague drops) A solution of equal parts arsenic acid and bicarbonate of potassa. Fossessed variety of uses, but chiefly for fevers. 

Potassium bicarbonate 4 183 KHCO3 Acid potassium carbonate bicarbonate of potassa hydrogen potassium carbonate monopotassic carbonate. 

Instead of 196 grains crystallized bicarbonate of potassa, may be used either 135 grains dry see No, 12) carbonate of potassa 281 grains crystallized carbonate of soda or 104 grains dry carbonate of soda. (See Ko, 80.)... 

By VLsing 981 grains (half the quantity) of the bicarbonate of potassa, obtain a still more delicate test liquid os each minim used for saturating a sample of acid roll represent only i of 1 per cent, of dry acid. 

Practical test of the strength of Acetic Acid. A less accurate, but more convenient method for practical purposee, is as follows —To 100 or lOOO parts (or groins) of a sample under inspection, add cautiously from a weighed quantity of powdered pure dry bicarbonate of potassa, sutficient to produce exact neutralization carefully re-weigh the bicarbonate unconsumed. Double the loss in gmins will indicate the percentage of acid in the liquid tested. 

Crystdlized carbonate of potassa. 87 Crystallized bicarbonate of potassa 100... 

Bicarbonate of Soda. This may be prepared from a solution of carbonate of soda treated in the same manner as for bicarbonate of potassa. (See Mo. 4183.) The XJ. S. Pharmacopoeia directs carbonate of soda iu small pieces to bo enclosed in a box (having on air-tight lid, and an inner bottom perforated with holes), and thus subjected, until saturated, to a stream of carbonic acid gas previously passed through water. 

Fowler s Solution Solution of Arsenite of Potassa. Boil grains ar-senious acid (in small pieces), and 64 grains bicarbonate of potassa, in 12 flnid ounces water, until tho acid is entirely dissolved. When cold, add i fluid ounce compound spirit of lavender, and sufBcient distilled water to make tho whole mixture measure a pint. (Cr.. V. Ph.)... 

Solutioii of Citrate of Potassa. Take of citric acid, h ounce, troy bicarbonate of potassa, 330 mins water, f pint. Dissolve the acid and bicarbonate In the water, and stnun the solution through muslin. (U. S, PA)... 

Remedy for Acidity of Stomach. This is a common symptom of weak or disordered digestion, and should bo treated with small doses 3 or 4 times daily of tbo carbonate or bicarbonate of potassa, soda, or ammonia or of sal-volatile or ammonia water, to which some tonio bitter may bo added. Diet should be light and nutritious, with os much out-door exercise os posiuble. The bowels should bo kept regular by the oooa sionnl use of some mild aperient. 

Braude states, that the salts of magnesia are mostly soluble in water, and bitter they are all soluble in hydrochloric acid their aqueous solutions are precipitated by potassa and soda, the precipitate, being soluble In hydrochloric, nitric, and sulphuric acids, and in hydroohlorate, nitrate, and sulphate of ammonia. Ammonia only throws down part of the magnesia, and forms a double salt, and carbonates of potassa and soda only throw down part of the magnesia, except the solution be hentad, when pearly the whole is precipitated. Chloride of ammonium redissolves tiro deposit, and when previously added to the magnesian solution, no precipitate ensues on adding the alkaline carbonates, unless the liquor be warmed The bicarbonates of von. ir. 

The following equation explains the reaction of oxalate of potassa the salt is assumed to1 bo. noutral on bicarbonate and sulphate of lima —... 

Carbonate op Zino.—The preparation of the neutral carbonate of oxide of zino is somewhat difficult, owing to the feeble affinity of the oxide for carbonic aoid. If, however, the precipitate which occurs on adding a solution of bicarbonate of soda or of potassa to a solution of zino bo, after waeliing, disseminated in water, and carbonic aeid oharged Into tho liquor, the precipitate is dissolved in tho form, of a bicarbonate, and on evaporating the liquid in an atmosphere of carbonic aeid, the neutral or monocarbonate of oxide of zino is obtained. Its formula is ZnO, C0S. 

Bicarbonate ofPotaesa. Bis-solvo 48 ounces carbonate of potassa in 10 pints distilled water pass carbonic acid gas through the solution to saturation (tho gas may bo evolved from chalk by diluted oil of vitriol). Filter, and evaporate, that crystals may form, at a heat not exceeding 160 Fahr. decant tho clear, and dry tho c stals. (U, JS. Ph.)... 

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