Potassii Citras, K 3 C 6 H 5 O 7 H 2 O. 

 3KHCO 3 + H 3 C 6 H 5 7 = K 8 C 6 H 5 O 7 + 3H 2 O + 3CO 8 . 



Potassium Citric Acid. Potassium Water. Carbon 



Bicarbonate. Citrate. Dioxide. 



Acidum Tartaricum, H 3 C 4 H 4 O 6 . 



Made by purifying argols, and converting the 

 cream of tartar into a calcium salt by means of 

 CaCOg and CaCl, decomposing the resulting Ca, tar- 

 trate with diluted H 2 SO 4 and allowing the filtered 

 solution to crystallize. 



Acidum Benzoicum, HC 7 H 5 O 2 



Found naturally in benzoin, balsam of peru and 

 other resinous substances. 



Ammonii Benzoas, NH 4 C 7 H 5 O 2 

 HC 7 H 5 O 2 + HN 4 HO = NH 4 C 7 H 5 O 2 -f H 2 O. 



Benzoic Water of Ammonium Water. 



Acid. Ammonia. Benzoate. 



Acidum Tannicum, C 14 H 10 O 9 



Tannic acid exists in many vegetable substances, 

 such as oak bark, salix, kino, catchu, etc., but the 

 officinal acid is obtained from nutgalls. 



CHEMICAL FORMULAE. 



We give below a few Chemical Formulae which 

 are in common use in Pharmaceutical Literature, and 

 should be learned. 



Acid Boric H 3 BO 3 



Acid Carbonic H 2 CO 3 



Acid Hydrochloric H Cl 



Acid Nitric HNO, 



Acid Nitrous HNO, 



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