Why copper (i) complex ions are not colored?
when electrons can be energized a bit, often visible light is capable of supplying sufficient energy. copper +2 has 9 electrons of equal energy in its third D-orbitals when dissolved in sufficient water, Cu+2 forms a complex ion with water molecules. when it forms a complex with 6 H2O's , the H2O ligands bond to the copper central atom with an octahedral geometry those bonds are covalent
