172 INORGANIC AGENTS 



Properties, — An amorphous, white powder, without odor 

 or taste. It gradually absorbs carbon dioxide from the air. 

 Insoluble in water or alcohol. 



Do8e,—B, & C, 3i.-ii. (4.-8); D., gr.v.-x. (.3-.6). 



PREPARATION. 



Uugventum Zinci Oxidi. Ointment of Zinc Oxide. (U. S. & B. P.) 

 Zinc oxide, 200; benzoinated lard, 800. (U. S. P.) 



ZiNOi AcETAS. Zinc Acetate. Zn (C2H302)j + 2 H2O. 

 (U. a & B. P.) 



Derivation. — Dissolve zinc oxide in diluted acetic acid 

 and boil. 



ZnO + 2 HC2H3O2 = Zn {GMzO,\ + H^O. Evaporate 

 and crystallize. 



Properties. — Soft, white, six-sided monoclinic plates, of 

 a pearly lustre, having a faintly acetous odor, and an astrin- 

 gent metallic taste. Exposed to the air the salt gradually 

 effloresces and loses some of its acid ; reaction acid ; soluble 

 in 2.7 parts of water and in 36 parts of alcohol. 



Incompatihles. — Same as sulphate. 



Z>ose. —^^Same as sulphate. 



ACTION OF THE ZINC SALTS. 



External. — The salts of zinc (except the chloride) have 

 an astringent action on raw surfaces and mucous membranes, 

 notably the sulphate and acetate. Absorption is not followed 

 by poisoning. They resemble other astringents, but do not 

 possess the sedative qualities of the lead salts, nor the local 

 alterative properties of silver nitrate. 



Internal. — In the alimentary tract very large doses of 

 tlie sulphate or acetate may induce gastro-enteritis, which 

 is to be treated with demulcents and alkaline carbonates in 

 order to form insoluble compounds. Vomiting will relieve 

 carnivora ; otherwise the stomach pump must be resorted to. 



Zinc salts apparently pioduce no remote effects upon 

 the body in medicinal doses, although in man chronic 



