Respuesta :
Answer:
A. Sodium (Na)
Explanation:
The total number of electrons in the outermost principal energy level of an element is called the valence electrons of that element.
Na (11)---→1s2 2s2 2p6 3s1
There 1 electron in the outermost principal energy level of Sodium. So, the number of valence electron of Sodium is 11.
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Answer:
Na
Explanation:
I was learning about it recently, that dude's right, it's Sodium