Question

Explain why the solution containing hydrated Ti³⁺ ion is purple in colour.

Answer 1

i. In [Ti(H₂O)₆] ³⁺, Ti³⁺ has 3d¹ configuration.

ii. This one electron will occupy one of the orbitals of lower energy and the complex (ion) will absorb suitable wavelength of white light and promote the electron from lower energy level to higher energy level.

iii. Since the complex absorbs light around 500 nm region, yellow and green lights are absorbed to excite the electron and the transmitted light is of the complementary colour i.e., red blue (purple).

iv. Hence, the solution containing hydrated Ti³⁺ ion is purple in colour.