MCQ
An atom of an element has one electron in the valence shell. It can be represented as:
- A6A12
- B19A39
- C13A27
- D12A24
✓
Answer
- 19A39
Explanation:
The atomic no. of 6A12 is 6. Its electronic configuration is 1s22s22p2. It has 4 electrons in valence shell.
The atomic no. of 19A39 is 19. Its electronic configuration is 1s22s22p63s23p64s1. It has 1 electron in valance shell.
The atomic no. of 13A27 is 13. Its electronic configuration is 1s22s22p63s23p1. It has 3 electrons in valence shell.
The atomic no. of 12A24 is 12. Its electronic configuration is 1s22s22p63s2. It has 2 electrons in valence shell.
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