14 
Original Communications. 
ART. IV. — ON ACETATE OF ZINC. By Ambrose Smith. 
(Extract from thesis. Phil. Coll. Phar.) 
Acetate of Zinc, in crystals, was first described by Glauber. 
A solution of this salt, obtained by the mutual decomposition 
of acetate of lead and sulphate of zinc, has long been used 
medicinally, and is officinal in the Edinburgh College of Phar- 
macy. In the crystalline state it was first made officinal, in 
the U. S. Pharmacopoeia of 1830. It is prepared according 
to this pharmacopoeia, by mixing solutions of acetate of lead 
and sulphate of zinc, filtering and evaporating the clear li- 
quid. The formula is as follows : 
" Take of sulphate of zinc 6 oz. 
acetate of lead 8 oz. 
distilled water, a gallon. 
Dissolve the sulphate of zinc and acetate of lead severally, in 
four pints of the distilled water; then mix the solutions and 
filter through paper ; lastly evaporate the filtered liquor so 
that upon cooling it may crystallize." Acetate of lead is com- 
posed of one equivalent of acetic acid, 51, one of protoxide 
of lead, 112, and three of water, 27=190. Sulphate of zinc 
of one equivalent of sulphuric acid, 40, one of oxide of zinc, 
42, and seven of water, 63=145. In this process one equi- 
valent of acetic acid, 51, from the acetate of lead unites with 
one equivalent of oxide of zinc, 42, and seven of water, 63, 
forming one equivalent of crystallized acetate of zinc, 156; 
and one equivalent of sulphuric acid, 40, from the sulphate 
of zinc unites with the equivalent of oxide of lead, 112, libe- 
rated by the decomposition of the acetate, forming one equi- 
valent of sulphate of lead, 152, which is separated by filtra- 
tion. Three of the ten equivalents of water of crystallization, 
contained in the salts employed, are of course lost in the pro- 
cess. The equivalent proportion of acetate of lead for the 
six ounces sulphate of zinc employed is 7 oz. 6 drs. 53.8 grs., so 
that a slight excess of the acetate is directed by the Phar- 
macopoeia. 
