Chemistry - Coordination Chemistry Question with Solution | TestHub
When an electron from a lower energy d orbital is excited to a higher energy d orbital, the energy of excitation corresponds to the frequency of light absorbed. This frequency generally lies in the visible region.
The color observed corresponds to the complementary color of the light absorbed.
Consider an aqueous solution of the complex of a 3d-series metal ion: ²⁻, ²⁺, and ²⁺ are have different colour ; one of them is red other are yellow and blue.
for transition is decreased when is converted to :
Options:(select one or more)
Answer:
Solution:
For d–d transitions:
So, higher crystal field splitting () higher energy smaller wavelength ( decreases).
Now compare ligand field strength (spectrochemical series):
Cl⁻ < F⁻ < H₂O < NH₃ < NO₂⁻
Given ²⁺, we need species with stronger field than H₂O, so will decrease.
Check options:
³⁺ (A) → higher oxidation state stronger field decreases
⁴⁻ (B) → NO₂⁻ strong field ligand decreases
⁴⁻ (C) → F⁻ weaker than H₂O increases
²⁻ (D) → Cl⁻ very weak field increases
Final answer: A, B (correct)