3D - 2

Which electron configuration is more stable: 3d(4) 4s(2) or 3d(5) 4s(1)?

Okay i didn't know how to show exponents so the exponents are in the parentheses

Public Comments

1. 3d(4) 4s(2) sublevels are all full
2. the 3d5 4s1 electron configuration is actually more stable certain electron arrangements have extra stability - they are (in increasing stability) 1) a random arrangement of electrons 2) a half-filled sublevel 3) a filled sublevel 4) a filled energy level the 3d5 4s1 configuration has 2 half filled sublevels whereas the 3d4 4s2 configuration is just a random arrangement
3. Certainly 3d(5) 4s(1). The sublevels are filled. Quote: Instead of [Ar]4s23d4 the electron configuration is [Ar]4s13d5. We might suggest that a half-filled d sublevel has extra stability