Which noble gas has the same electron configuration as the oxygen atom in a water molecule?

• A. Helium (He)
• B. Argon (Ar)
• C. Neon (Ne)
• D. Krypton (Kr)

Answer: (C)

Verified step by step guidance

1. Understand that the question is asking for a noble gas with the same electron configuration as the oxygen atom in a water molecule. The oxygen atom in water has the same electron configuration as a neutral oxygen atom, since bonding does not change the total number of electrons in the atom itself.
2. Recall the electron configuration of an oxygen atom, which has 8 electrons. The configuration is \$1s^2 2s^2 2p^4$.
3. Identify the noble gases and their electron configurations: Helium (He) has 2 electrons (\$1s^2\(), Neon (Ne) has 10 electrons (\)1s^2 2s^2 2p^6$), Argon (Ar) has 18 electrons, and Krypton (Kr) has 36 electrons.
4. Recognize that the noble gas with the closest electron configuration to oxygen is Neon (Ne), which has a full \$2p$ subshell, representing a stable, filled shell configuration.
5. Conclude that the oxygen atom's electron configuration is similar to Neon (Ne) if you consider the oxygen atom gaining 2 electrons to complete its valence shell, which is why Neon is often used as a reference for a full octet in oxygen.