The electronic configuration of Eu (Atomic No. 63), Gd (Atomic No. 64) and Tb (Atomic No. 65) are -

Options

A. `[Xe]4f^(7)6s^2, [Xe]4f^8 6s^2 and [Xe]4f^85d^16s^2`
B. `[Xe]4f^(7) 5d^(1)6s^(2), [Xe]4f^7 5d^1 6s^2 and [Xe]4f^9 6s^2`
C. `[Xe]4f^7 6s^2,[Xe]4f^75d^1 6s^2 and [Xe]4f^8 5d^1 6s^2`
D. `[Xe]4f^7 6s^2, [Xe]4f^(1)5d^(1) and [Xe]4f^9 6s^2`

Answer

D

Explanation

`Eu(63) = [Xe]4f^7 5d^16s^2`
`Tb(65) = [Xe] 4f^9 6s^2`