PARIS GREEN 



Paris green closely approximates the for- 

 mula Cu(C2H302)2 • 3Cu(As02)2, which was 

 assignd it by Ehrmann in 1834, and is cald 

 an aceto-arsenite of copper. There are two 

 general processes for making it, first replacing 

 most of the acetate ion of copper acetate by 

 the arsenite ion of arsenious acid ; and second, 

 replacing some of the arsenite ion of copper 

 arsenite by the acetate ion of acetic acid. 

 The latter process is followd in these direc- 

 tions. 



Procedure. — Dissolv 9 grams of dry 

 carbonate of soda, or 24 grams of hydrous, in 

 a beaker or porcelain d'sh in 80 cc. of water. 

 Into this solution sprinkle gradually 16 

 grams of arsenious oxid, and boil until the 

 acid has united with the soda as shown by 

 solution of the resulting sodium arsenite. 



Dissolv 20 grams of copper sulfate in 80 

 cc. of water. When both of the solutions 

 are at about 60° — as warm as the hand can 

 comfortably bear — pour the sodium arsenite 

 solution into the copper sulfate. Add 10.5 

 cc. of 50 per cent acetic acid — or an equiva- 

 lent of any other strength, and allow the 



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