Why first ionization energy of transition element of which transition is higher?
Answers
As the number of protons increase within a period (or row) of the periodic table, the first ionization energies of the transition-metal elements are relatively steady, while that for the main-group elements increases. The effective nuclear charge mirrors and may explain the periodic trends in the first ionization energies of the transition-metal and main-group elements. The differing periodic trends in the effective nuclear charge are due to a greater increase in shielding in the transition-metal elements than in the main-group elements. The difference in shielding is due to the entry of electrons into an inner-shell orbital for the transition-metal elements, while electrons enter an outer-shell orbital for the main-group elements.
Explanation:
The ionization energy increases due to the increase in the nuclear charge with an atomic number at the beginning of the series.
- Gradually, the shielding effect of the added electrons also increases.
- These two opposing factors lead to a rather gradual increase in the ionization energies in any transition series.