Question

JEE MAINS CHEMISTRY QUESTION SEPTEMBER 2020

Answer 1

The values of the crystal field stabilization energies for a high spin d⁶ metal ion in octahedral and tetrahedral fields, respectively, are :

1. -0.4 ∆₀, -0.6∆₀
2. -0.8∆₀, -0.6∆₀
3. -0.4∆₀ , -1.2∆₀
4. -0.4∆₀ , 0.27∆₀

solution : for high spin octahedral complex,

configuration of d⁶ will be t_2g⁴, e_g² , [ it is shown in figure. ]

now the Crystal field stablization energy, CFSE = 2 × (+ 0.6 ∆₀) + 4 × (-0.4∆₀) = -0.4∆₀

for high spin tetrahedral complex,

condition of d⁶ will be t_2g³, e_g³ [ it is shown in figure ]

now the Crystal field stabilization energy, CFSE = 3( + 0.4 ∆₀) + 3( - 0.6∆₀) = -0.6∆₀

Therefore the correct option is (1) -0.4 ∆₀, -0.6∆₀