Practise explaining ionisation-energy differences using nuclear charge, atomic radius, inner-electron shielding and repulsion between paired outer electrons.
The second ionisation energy of oxygen is greater than the second ionisation energy of fluorine.
Which factor explains this difference?
The atomic radius of an oxygen atom is smaller than that of fluorine.
The covalent bond in a fluorine molecule is weaker than the bond in an oxygen molecule.
A spin-paired electron is removed from fluorine but not from oxygen.
Fluorine has more electrons in total than oxygen. This causes a greater shielding of the nuclear attraction in fluorine.
C