Question

The electronic configurations of Eu(Atomic No. 63), Gd(Atomic No. 64) and Tb (Atomic No. 65) are
(a) [Xe]4f⁷ 6s², [Xe]4f⁸ 6s² and [Xe]4f⁸ 5d¹ 6s²
(b) [Xe]4f⁷ 5d¹ 6s², [Xe]4f⁷ 5d¹ 6s² and [Xe]4f⁹ 6s²
(c) [Xe]4f⁶ 5d¹ 6s², [Xe]4f⁷ 5d¹ 6s² and [Xe]4f⁸ 5d¹ 6s²
(d) [Xe]4f⁷ 6s², [Xe]4f⁷ 5d¹ 6s² and [Xe]4f⁹ 6s²

Answer 1

D IS CORRECT ANSWER........

Answer 2

${\huge {\mathfrak {Answer :-}}}$

➡️ Option (D)

That's it..