Question

Which element has seven energy levels the only one valence electron

Answer 1

Your answer is chlorine.

Step-by-step explanation:

Valence electrons help in predicting chemical reactions. For example, since hydrogen (H) is in group 1, it has 1 electron in its outer energy level. Chlorine (Cl), which is in group 17, has 7 electrons in its outer energy level and is one electron short of having a "full" outermost energy level.

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