MCQ
Which electronic configuration must represent an atom in an excited state?
- A$1s^2 ,2s^2 2p^1$
- B$1s^2 ,2s^2 2p^2$
- ✓$1s^2 ,2s^22p^2 ,3s^1$
- D$1s^2 ,2s^2 2p^5$
✓
Answer
Correct option: C.
$1s^2 ,2s^22p^2 ,3s^1$
c
$(c)\, 1s^2,2s^22p^2,3s^1$ (Excited state)
$(c)\, 1s^2,2s^22p^2,3s^1$ (Excited state)
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