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In lecture, we learned that ionization energies increase across a period because the effective nuclear charge increases. I understand this, but since more electrons are added across a period, shouldn't the shielding effect from those electrons also increase? And wouldn't this prevent the ionization energies from increasing across a period?
I guess the increase in nuclear charge trumps the electron shielding. Maybe because when increasing across a period, the electrons added are valence electrons, so I think the electron shielding really isn't increasing much.
As you move from left to right across a period the nuclear charge of an atom increases, which trumps the shielding effect. Thus, ionization energy tends to increase across a period due to this increase in charge across a period.
ionization energy is the energy required to remove an electron from an atom in the gas phase. The further away an electron is from the nucleus the easier it is to remove. Ionization energy increases across a period because the nuclear charge is greater and the electrons are still being added to the SAME shell so the effective charge is getting bigger. This is why the shielding effect does not also increase. For me, I think of the shielding effect as coming into play when we are adding shells AKA moving down a group--> this is why ionization energy decreases as we move down a group, because the attraction the outermost e- feel to the nucleus is not as strong because of shielding happening. Sorry if that was confusing, hope it helps.
Ionization energy is the energy required to remove an electron from an atom in gas phase. Going across a period, you are increasing the number of photos while the number of shielding electrons (inner electrons) stay constant. So there will be an increase of effective nuclear charge, a tighter hold on the outer electrons and thus higher IE.
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