Define ionization energy
The energy required to remove an electron from an atom.
Why do atoms get easier to ionize down a group?
Their electrons are farther from the nucleus and more shielded.
How does effective nuclear charge affect ionization energy?
An effective nuclear charge increases ionization energy.
Which element in Period 2 has the highest first ionization energy?
Neon
Does ionization energy increase or decrease across a period?
Increases across a period
Which element has the highest ionization energy on the periodic table?
Helium
Which loses an electron more easily potassium or calcium?
Potassium
Between sodium and magnesium, which has the higher ionization energy?
Magnesium
Does ionization energy increase or decrease down a group?
Decreases down a group.
What happens to ionization energy when the atomic radius gets smaller?
Ionization energy increases.
Why does oxygen have a lower ionization energy than nitrogen?
Oxygen has paired electrons that create repulsion.
Which Group 1 element has the lowest ionization energy?
Francium
What kind of elements usually have the lowest ionization energy?
Metals
Why do noble gases usually have very high ionization energies?
They have full valence shells and are very stable.
Which has the highest ionization energy in Period 3?
Argon
Which element would require more energy to remove an electron: sulfur or chlorine?
Chlorine
Why do atoms with high ionization energy hold electrons tighter?
Their nuclei pull strongly on electrons.
What role does shielding play in ionization energy?
Shielding lowers ionization energy because inner electrons block the nucleus’s pull.
Why is removing a second electron always harder than removing the first?
The atom becomes more positive and holds the remaining electrons tighter.
An element is in Group 18 and Period 3. Would you expect it to have a high or low ionization energy? Name the element too.
High ionization energy; the element is Argon