Copper Ammonio Solution

Characters and Tests.—Heavy, white, glistening powder, or in translucent masses resembling porcelain. Completely volatile at 400° F. Sublimed in a test-tube, it condenses in brilliant octahedral or triangular crystals. Its aqueous solution furnishes a yellow precipitate (silver arsenite) with silver ammonio-nitrate, and a green precipitate (copper arsenite) with copper ammonio-sulphate. These precipitates are soluble in ammonia and in nitric acid. 

Characters and Tests.—Blue crystalline salt, in oblique prisms, soluble in water, forming a pale blue solution which strongly reddens blue litmus. The aqueous solution gives with barium chloride a white precipitate (barium sulphate), insoluble in hydrochloric acid, showing the salt to be a sid-phate and with potassium ferrocyanide a maroon-red precipitate, indicating the presence of copper (cupric ferrocyanide). If an aqueous solution of the salt be mixed with twice its volume of chlorine water, to peroxidize any iron that may be present, and solution of ammonia be added, the precipitate (cupric hydrate) formed by the first addition of the ammonia will be dissolved by a further and sufficient addition of the alkali, and a violet blue solution (copper ammonio-sulphate) will be produced, leaving nothing un ssolved unless iron be present, in which case a reddish-brown precipitate will be left. 

It is interesting to note that, if freshly precipitated and thoroughly washed Cu(OH)2 is treated with ammonia, a similar deep blue solution is obtained, but in this case the negative ions are hydroxyl instead of sulphate. Ammonio-copper hydroxide is very soluble and very highly ionized, and the solution compares in basic strength with one of sodium hydroxide. 

Cupric hydroxide is nearly insoluble in NaOH solution alone, but it dissolves when a soluble tartrate is added, the copper going into a complex negative ion similar in color to the ammonio-cupric ion. 

What is an ammoniate Give the formulas of the ammonio-ions of copper, silver, zinc, and cadmium. How can crystallized ammonio-copper sulphate be prepared How would you make a solution of ammonio-copper hydroxide What is the alkaline strength of such a solution ... 

Solution of Amznonio-Sul-phate of Copper, Dissolve 1 drachm of tho ammonio-sulphate in 1 pint water, and filter. This is stimulant and detergent. Ap-pbed as a lotion to indolent ulcers and, largely diluted, to remove specks on tho cornea. Also used as a test for arsenical compounds, with which it throws down a groen precipitate. 

Fibroin—Sericin—is obtained from silk by removal of fat, albumin, coloring matters, etc., by the proper solvents. It dissolves, like cellulose, in ammonio-sulfate of copper solution. It does not contain S, and resembles gelatin in its chemical composition. 

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