Question

Chromium (Z = 24) has electronic configuration
a) [Ar] 4d⁴ 4s²
b) [Ar] 4d⁵ 4s¹
c) [Ar] 3d⁵ 3s¹
d) [Ar] 3d⁵ 4s¹

Answer 1

$[Ar]3d{}^{5}4s{}^{1​}$

Electron orbitals are most stable when they are fully filled or half filled. So the most stable configuration for the 3d subshell is $3d{}^{10} or 3d{}^{5}$

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Answer 2

Chromium (Z = 24) has electronic configuration and the Electronic configuration of chromium (Z=24) is (d) [Ar] 3d5 4s1.

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