Schweizer's reagent
（重定向自Tetraamminecopper dihydroxide）
![Ball-and-stick model of the tetraamminediaquacopper (II) cation, [Cu(NH3)4(H2O)2]2+](/uploads/202502/15/Tetraamminediaquacopper(II)_cation_3D_ball5141.png)
Schweizer's reagent is the chemical complex tetraamminediaquacopper dihydroxide, [Cu(NH3)4(H2O)2](OH)2. It is prepared by precipitating copper(II) hydroxide from an aqueous solution of copper sulphate using sodium hydroxide or ammonia, then dissolving the precipitate in a solution of ammonia.