The correct electronic configuration of Cr (Z - 24) is:
Correct answer: B. [Ar] 4s1 3d5
- A. [Ne] 4s2 3d5
- B. [Ar] 4s1 3d5
- C. [Ne] 4s2 3d6
- D. [Ar] 4s2 3d4
Explanation
The correct electronic configuration of Cr (Z = 24) is [Ar] 4s1 3d5. The Aufbau principle states that electrons fill orbitals in order of increasing energy. The 3d orbitals are lower in energy than the 4s orbitals, but the 3d orbitals are only half-filled in Cr, which makes them more stable than the 4s orbitals that are fully filled. Therefore, the electron configuration of Cr is [Ar] 4s1 3d5.
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