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Question
Indicate the number of unpaired electron in:
Cr (Z = 24)
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Solution
Cr (Z = 24): 1s2 2s2 2p6 3s2 3p6 4s1 3d5
Orbital diagram:
| ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑ | ↑ | ↑ | ↑ | ↑ | ↑ |
| 1s | 2s | 2p | 3s | 3p | 4s | 3d | ||||||||
Number of unpaired electrons = 6
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