The atomic number of an element is 18. The number of electron pairs in its valence shell is:
Correct answer: B. 4
- A. 3
- B. 4
- C. 6
- D. 8
Explanation
The electronic configuration of an element with atomic number 18 is given by: 2,8,8Hence, it is clear that there are 4 electron pairs (8 electrons) in its valence shell. All other options are incorrect.
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