MCQ
Assuming that elements are formed to complete the seventh period, what would be the atomic number of the alkaline earth metal of the eighth period?
- A$113$
- ✓$120$
- C$119$
- D$106$
✓
Answer
Correct option: B.
$120$
b
$7^{th}$ period ends in $118$
$7^{th}$ period ends in $118$
hence the alkaline earth metal shall belong to the second group, thus its atomic number would be : $120\{$ Option $B\}$
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