3.4 Transition metal complexes

If red/orange region is absorbed, what is the color that we see. Refer to color wheel

• Red
• Orange
• Blue
• Yellow

If violet region is absorbed, what is the color that we see. Refer to color wheel

• Violet
• Orange
• Blue
• Yellow

Color of metal complexes are due to the following factors EXCEPT

• Types of ligands
• Nature of transition metal
• Oxidation states
• Type of orbitals

3d orbitals are degenerate. What does it means?

• All 3d orbitals are in same order
• All 3d orbitals have different electron arrangement
• All 3d orbitals are in the same energy level
• All 3d orbitals have the same shape

Ti³⁺ solution in the presence of water, is violet in color. Why?

• Presence of water ligands cause color formation
• Electron can be excited
• Wavelength of light can be absorbed
• Presence of water ligand cause the splitting the 3d orbitals

Sc³⁺ solution in the presence of water is colorless. Why?

• Presence of ligands cause the splitting of 3d orbital.
• There is no splitting of 3d orbitals
• There is no electrons to be excited
• Energy level is too high for electron to reach

Zn²⁺ solution in the presence of water is colorless. Why?

• Presence of ligands cause the splitting of 3d orbital.
• There is no splitting of 3d orbitals
• There is no electrons to be excited
• 3d orbitals are fully filled and no electrons can be excited

Cu²⁺ solution in the presence of water is blue. Why?

• Splitting of 3d orbital and electron can be easily excited
• Blue light is aborbed to excite elec to higher energy level
• Blue light is emitted when elec move to lower energy level
• 3d orbital are partially filled and electrons can be excited

The following statements are true about spectrochemical series EXCEPT

• CN^- ion is the strongest ligand
• Strong ligand displaces weak ligand
• Strong ligand causes greater split in 3d orbital
• Weak ligand will not split the 3d orbital

Strong ligand causes a greater split of 3d orbital because

• greater repulsion between ligands and 3d electrons
• strong ligand has greater energy
• strong ligand causes a greater displacement
• strong ligand has greater electron density