Exercise 103. Gel of Cupric Hydroxide

Prepare 50 cc. of a solution of copper acetate saturated at room temperature. Prepare also a solution of ammonia by diluting the concentrated reagent with an equal volume of water. 

To 50 cc. of the solution of copper acetate add four drops of concentrated sulfuric acid and then, with constant stirring, slowly add 3 to 4 cc. of the dilute ammonia. The mixture sets to a light blue gel of copper hydroxide, that will stand up for a week or more under favorable conditions. 

References Mellor, III, 142 Friend, II, 278 Finch, J. Phys. Chem., 18,26 (1914) Weiser, The Hydrous Oxides, p. 144 (1926) Paal and Steyer, Kollmd-Zeit., 30, 1 (1922). 

Additional Exercise Gel of mercuric oxide, Bunco, J. Phys. Ckem., 18, 269 (1914). 

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