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Question
What are the atomic numbers of elements whose outermost electrons is represented by 3p5?
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Solution
3p5
Completing the electron configuration of the element as
1s2 2s2 2p6 3s2 3p5
∴ Number of electrons present in the atom of the element = 2 + 2 + 6 + 2 + 5 = 17
∴ Atomic number of the element = 17
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