Question

JEE Mains Chemistry question is attached

Answer 1

The crystal field configuration of complexes [Ru(en)₃]Cl₂ and [Fe(H₂O)6]²⁺ respectively is ...

solution : we know, splitting of crystal field depends on the field produced by the ligands and the charge on metal ion .

experimentally, order of field strength of given ligands is H₂O < (en)

so, [Ru(en)₃]Cl₂ is low spin complex

now for Ru²⁺ , configuration of d = 4d⁶

from crystal field theory, 4d⁶ = t_(2g)⁶, e_(g)⁰

and [Fe(H₂O)6]²⁺ is high spin complex

now for Fe²⁺ , configuration of d = 3d⁶

from crystal field theory, 3d⁶ = t_(2g)⁴, e_(g)²

Therefore the configuration of [Ru(en)₃]Cl₂ and [Fe(H₂O)6]²⁺ respectively is t_(2g)⁶, e_(g)⁰and

t_(2g)⁴, e_(g)² .

so the correct choice is option (2) .