Question

Which ligand generates the smallest d-d splitting when bound to a transition metal and does not show electronic transitions in the visible light region?

a. SO₄²⁻
b. NH₃
c. CN
d. H₂O
e. pyridine

Answer 1

The ligand among the options given that generates the smallest d-d splitting when bound to a transition metal and usually does not absorb in the visible light region is water (H2O).

Therefore the correct answer option d. H₂O

Step-by-step explanation:

The question concerns which ligand creates the smallest d-d splitting in the spectrochemical series when bound to a transition metal and is not observed through electronic transitions in the visible light region. Based on the spectrochemical series, the ligand that causes the smallest d-d splitting is the one with the weakest field strength. Among the options given (SO42-, NH3, CN-, H2O, and pyridine), water (H2O) is the correct answer because it is the ligand with the weakest field strength and thus generates the smallest d-d splitting. This means it won't easily absorb visible light to promote electrons between d-orbitals, and most of its absorption occurs in the ultraviolet region rather than the visible spectrum.