The first six ionization energies of a first-row transition metal are shown below
CHEMISTRY · Multi-part · A Level · Chemistry · Transition metals and their chemistry · Transition metals and their chemistry
Problem
The first six ionization energies of a first-row transition metal are shown below.
Ionization step (n) 1 2 3 4 5 6
Ionization energy (kJ mol⁻¹) 650 1300 2450 7700 9900 11500
Answer the following questions regarding the electronic structure of the atom and trends in its successive ionizations.
(a) Determine after which ionization step the atom is likely to have lost all of its valence electrons, and justify your choice with reference to the data.
(b) Propose an electron configuration for the neutral atom that is consistent with the data, using noble-gas core notation.
(c) Provide a detailed explanation for why the jump from the third to the fourth ionization energy is so much larger than the increase from the second to the third, incorporating arguments about subshell stability and the penetration of 3d versus 4s electrons.
(d) Design an experiment, using any standard spectroscopic or mass-spectrometric technique, that could supply additional evidence to confirm your proposed electronic configuration. Outline the key measurements and the expected outcomes that would support your explanation in part (c).