What do you observe when blue coloured copper hydroxide reacts with the excess of ammonium hydroxide?
The correct option is C.
A deep blue solution of tetraamine copper hydroxide is formed.
When copper hydroxide reacts with the excess of ammonium hydroxide, a deep blue solution of tetrammine copper hydroxide is obtained.
Cu(OH)2 (ppt)+NH4(OH)2 (excess)→4H2O+[Cu(NH3)4](OH)2(deep blue solution)