MCQ
The nucleus of an element contain $ 9 $ protons. Its valency would be
- ✓$1$
- B$3$
- C$2$
- D$5$
✓
Answer
Correct option: A.
$1$
a
(a) Since its nucleus contain $9$ proton so its. atomic number is $ 9$ and its electronic configuration is $ 2, 7. $ So it require one more electron to complete its octet. Hence its valency is $1.$
(a) Since its nucleus contain $9$ proton so its. atomic number is $ 9$ and its electronic configuration is $ 2, 7. $ So it require one more electron to complete its octet. Hence its valency is $1.$
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