electronic configuration

Question

The electronic configuration of chromium (Z = 24) is:

RankGuru · Accepted Answer

Expected configuration using Aufbau principle for $Z=24$ is $[Ar] 3d^4 4s^2$.
However, **Chromium ($Cr$)** and **Copper ($Cu$)** show anomalous configurations due to the extra stability of **half-filled** and **completely filled** subshells.
- In $Cr$, an electron from the $4s$ orbital jumps to the $3d$ orbital to make $3d^5$ (exactly half-filled) and $4s^1$ (exactly half-filled).
- Correct configuration: $[Ar] 3d^5 4s^1$.

Rank Guru

electronic configuration

Select the correct option:

More electronic configuration Practice Questions

The number of unpaired electrons in Fe²⁺ (Z = 26) is: