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Question
What are the atomic numbers of elements whose outermost electrons is represented by 3s1.
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Solution
3s1
Completing the electron configuration of the element as
1s2 2s2 2p6 3s1.
∴ Number of electrons present in the atom of the element
= 2 + 2 + 6 + 1 = 11
∴ Atomic number of the element = 11
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