Question

The electronic configuration of $ Fe_{26} $ is $[Ar]$:

• A. $3 d^{8} 4 s^{2}$
• B. $3 d^{7} 4 s^{2}$
• C. $3 d^{6} 4 s^{2}$
• D. $3 d^{5} 4 s^{2}$

Answer 1

Answer: (C)

Electrons are filled, in orbitals according to aufbau rule,
${ }_{26} F e=1 s^{2}, 2 s^{2}, 2 p^{6}, 3 s^{2}, 3 p^{6}, 4 s^{2}, 3 d^{6}$