Question:
The electronic configuration of an element is 2,8,7. What is the atomic number of the element?
The electronic configuration of an element is 2,8,7. What is the atomic number of the element?
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The atomic number of an element is equal to the total number of electrons in a neutral atom.
Updated On: Oct 27, 2025
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- 11
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The Correct Option is C
Solution and Explanation
The atomic number of an element is determined by the total number of electrons. Given the configuration \(2,8,7\), summing these gives:
\[
2 + 8 + 7 = 17
\]
This corresponds to chlorine (\(\text{Cl}\)).
Thus, the correct answer is \( \mathbf{(C) 17} \).
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