COPPER SULFATE 



Procedure. — Place in a beaker 10 grams 

 of metallic copper, 50 cc. of water, 15 to 18 cc. 

 of chamber sulfuric acid and 25 cc. of dilute 

 (sp. gr. 1.2, 32 per cent) nitric acid. Place 

 the mixture on asbestos, under a hood, and 

 heat gently with a low flame until the copper 

 is all dissolvd. This should require about 

 an hour. In case the solution becomes 

 saturated during the heating as evinst by 

 the crystals forming on the surface, add a 

 few drops of water. When the copper is all 

 dissolvd continue heating until the solution is 

 saturated, then remove the beaker, place it 

 in cold water and stir the solution as it cools 

 until crystalUzation is complete. Filter off 

 the crystals on a Witt plate. Evaporate 

 the filtrate to the point of crystallization and 

 cool the liquid until all the crystals have 

 formd that will. If possible pour out the 

 mother liquor, which consists mostly of strong 

 acids, and bring the remaining crystals onto 

 a Witt filter. Put both crops of crystals into 

 25 cc. of boiling water and adjust the quan- 

 tity of water, by adding directly and boiling 

 off, until the salt is all dissolvd and the solu- 



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