Question

A d-block element forms octahedral complex but its magnetic moment remains same either in strong field or in weak field ligand. Which of the following is/are correct?

• A. Element always forms colourless compound
• B. Number of electrons in $t_{2g}$ orbitals are higher than in $e_g$ orbitals
• C. It can have either $d^3$ or $d^8$ configuration
• D. It can have either $d^7$ or $d^8$ configuration

Answer 1

Answer: (B), (C)

The correct options are
B Number of electrons in $t_{2g}$ orbitals are higher than in $e_g$ orbitals
C It can have either $d^3$ or $d^8$ configuration

Number of electrons in $t_{2g}$ orbitals are higher than in $e_g$ orbitals as irrespective of nature of ligand field, magnetic moment of octahedral complexes having metal ions in $d^1,d^2,d^3,d^8,d^9$ configuration, remains same. Element may or may not form colourless complex.