CHEMISTRY · Single correct · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
Two hypothetical atoms, M and Q, each have one electron in a p subshell.
• Atom M: atomic number 13, number of core electrons 10, atomic radius 135 pm
• Atom Q: atomic number 5, number of core electrons 2, atomic radius 85 pm
Which statement correctly compares the magnitude of the attractive force between the nucleus and a valence electron in the two atoms?
(a) The force is greater in M because its higher nuclear charge exerts a stronger pull on the electron than in Q.
(b) The forces are approximately equal because both atoms have an effective nuclear charge of approximately +3 acting on the valence electron.
(c) The force is greater in Q because its valence electron is closer to the nucleus and experiences less shielding.
(d) The force is greater in M because electrons in a 3p subshell are more penetrating than electrons in a 2p subshell.