Which of the following elements is stable?
A. Carbon, atomic number 6
B. Neon, atomic number 10
C. Fluorine, atomic number 9
D. Boron, atomic number 5

Respuesta :

B. Neon, atomic number 10. 
B. Neon, atomic number 10 is the correct answer, because Neon is a noble gas, which already has 8 valence electrons.
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