Question

select the correct answer.
which of these elements has two electrons in its outer p orbitals?
a. helium (he)
b. barium (ba)
c. nitrogen (n)
d. silicon (si)
e. sulfur (s)

Explanation:

1. Analyze each element's electron configuration to find outer p orbital electrons:

• Helium (He): Atomic number 2, electron configuration $1s^2$. It has no p orbitals.
• Barium (Ba): Atomic number 56, electron configuration $[Xe]6s^2$. Its outer orbital is an s orbital, no p electrons.
• Nitrogen (N): Atomic number 7, electron configuration $1s^22s^22p^3$. It has 3 outer p electrons.
• Silicon (Si): Atomic number 14, electron configuration $1s^22s^22p^63s^23p^2$. It has 2 outer p electrons.
• Sulfur (S): Atomic number 16, electron configuration $1s^22s^22p^63s^23p^4$. It has 4 outer p electrons.

Answer:

D. silicon (Si)