# Changing solubility of metal complex by adding ethanol

After creating a solution of copper(II)-sulfate-pentahydrate, water and concentrated ammonia, the newly formed complex (tetraamminecopper(II)-sulfate-monohydrate) is completely dissolved in water. By adding ethanol, one is able to decrease the solubility of that complex in water and have crystals percipitates out of solution.

Since the complex is not soluble in ethanol, I am having trouble understanding why adding ethanol changes anything about the solubility of the complex. Would adding some organic phase like petrol ether or a non-soluble solid such as ceramic pellets do the same?

• Why tetraamminecopper(II)-sulfate-monohydrate is formed and not $\ce{[Cu(NH3)4(H2O)2]^2+}$? Oct 25, 2020 at 12:48