4CoSO4 + 2(NH4)2SO4 + 12(NH3•H2O) + O2 → 2[Co(H2O)2(NH3)4]2(SO4)3 + 6H2O
Cobalt(II) sulfate react with ammonium sulfate, ammonium hydroxide and oxygen to produce sulphate trance-tetraamminediaquacobalt(III) and water. The reaction proceeds at room temperature.