Copper hydroxide and schweizer's reagent

This is one of the first experiments I ever performed. If aqueous ammonia is added to a solution of copper sulphate a light blue precipitate of copper hydroxide is formed. If  more ammonia is added the precipitate redissolves yielding a dark blue solution of tetraamminediaquacopper(ii) dihydroxide.

This is what happens:
The ammonia reacts with the water in a reversible reaction to form hydroxide ions and ammonium ions
NH3 + H2O <==> NH4+ + OH-

and the Copper sulphate dissolves in water to give hexaaquacopper(ii) ions and sulphate ions
CuSO4.5H2O + H2O ==> [Cu(H2O)6] (2+) + SO4 (2-)

The hydroxide ions and hexaaquacopper(ii) ions combine to produce copper hydroxide which precipitates
[Cu(H2O)6] 2+ + 2OH- ==> Cu(OH)2.2H2O + 4H2O

If more ammonia is added, schweizer's reagent (tetraamminediaquacopper(ii) dihydroxide) is formed
Cu(OH)2.2H2O + 4NH3 ==> [Cu(NH3)4(H2O)2](OH)2

[Cu(H2O)6] +2 + 4NH3 + 2 OH- ==> [Cu(NH3)4(H2O)2](OH)2 + 4 H2O

Tetraamminediaquacopper(ii) dihydroxide is an interesting compound. Its capable of dissolving cellulose. It cannot exist in its pure state and is only stable in aqueous solution or under a stream of ammonia. I don't really have any use for it or copper hydroxide, although it is interesting dissolving cotton with schweizer's reagent. Here's some pictures:


From left to right: copper hydroxide, schweizer's reagent.