MCQ
The outer electronic configuration of radioactive element present in $\ce{IA}$ group is :
- A$\ce{8s^1}$
- ✓$\ce{7s^1}$
- C$\ce{5s^1}$
- D$\ce{6s^1}$
✓
Answer
Correct option: B.
$\ce{7s^1}$
The radioactive element in group $1A$ is francium $\ce{(Fr)}$ atomic number $87$ having electronic configuration $\ce{(Rn) 7s^1}$.
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