The table below lists the experimentally measured first ionization energies for the…
CHEMISTRY · Multi-part · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
The table below lists the experimentally measured first ionization energies for the first three elements in Period 2.
Element
Li
Be
B
I1 (kJ mol−1)
520
900
801
All three elements are in the gas phase and at the same temperature when the measurements are made.
(a) Describe the overall trend in first ionization energy across these three elements.
(b) Account for the increase in I1 from Li to Be in terms of atomic structure.
(c) Despite the general rise across a period, the ionization energy decreases from Be to B. Explain this deviation using electron configuration and any relevant inter-electron interactions.
(d) Predict whether the first ionization energy of carbon is expected to be greater than, equal to, or less than that of boron. Justify your prediction thoroughly.