Question

Explain giving reasons:

Cd⁺² salts are white.

Answer 1

1. Cd²⁺ ion has the electronic configuration [Kr] 4d¹⁰, which means it has completely filled d-orbitals.
2. Because of the full d-subshell (d¹⁰), no d-d electronic transitions are possible in Cd²⁺ compounds.
3. d-d transitions are responsible for the color in transition metal salts.
4. Without any d-d transitions, Cd²⁺ salts do not absorb visible light.
5. As a result, Cd²⁺ salts appear white or colorless.

Thus, the white color of Cd²⁺ salts is due to the absence of partially filled d-orbitals, preventing light absorption in the visible region.