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Question
Indicate the number of unpaired electrons in \[\ce{Si}\] (Z = 14).
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Solution
Electronic configuration of \[\ce{Si}\] (Z = 14) is 1s2 2s2 2p6 3s2 3p2
Orbital diagram:
| ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑↓ | ↑ | ↑ | |
| 1s | 2s | 2p | 3s | 3p | ||||
Number of unpaired electrons = 2
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