11 Which is the best explanation as to why heliurn has a higher ionization energy than argon? A Heliurn's valence energy level is closer to its nucleus than argon's; therefore the
electromagnetic attraction is stronger between the nucleus and the electrons.
B Heliurn's electrons move faster, so it is harder for another atom to remove them.
C Helium has a full valence energy level and argon does not.
D Heliumn has fewer neutrons than argon; therefore its electrons are more difficult to remove
from its electron cloud.