THE 
AMERICAN JOURNAL OF PHARMACY. 
JANUARY, 1846. 
ART. LXVIII. — OBSERVATIONS ON ACETATE OF ZINC. 
By William Procter, Jr. 
In the last edition of the United States Pharmacopoeia, 
the formula for preparing acetate of zinc was revised, the 
process by double decomposition between acetate of lead 
and sulphate of zinc was repudiated, and a new method 
adopted, which consists in precipitating the lead from a 
solution of acetate of lead, by introducing into it a quantity 
of metallic zinc. When the materials employed are pure, 
the salt can be obtained by this process with the utmost 
readiness, and in a beautifully crystallized form ; but if, as 
is often the case, the zinc employed contains iron, the salt 
is always contaminated with the acetate of that metal, 
which gives it a yellowish brown colour. The solution of 
acetate of zinc when first separated from the metal is colour- 
less, the iron in it being in the state of protoxide, but by stand- 
ing exposed to the air, or by heat, it gradually assumes the 
form of sesquioxide, and communicates colour to the so- 
lution. 
It is with a view to this condition that the Pharmacopoeia 
directs the addition of a filtered solution of chlorinated lime; 
the lime of the added salt displacing the ferruginous oxide, 
which is at once peroxidized by the action of the chlorine. 
This operation succeeds best when the iron is in its first, 
vol. xi. — NO. iv. 22 
