Answer:
F has a larger nuclear charge than[tex]O_2[/tex] account for the fact that the F-ion is smaller than the [tex]O_2[/tex]-ion
Explanation:
The 'effective nuclear charge' of an polyelectronic atom, denotes the net positive(+ve) charge that experienced by an electron. The "strength of the nuclear charge" can be determined based on the oxidation-number of an atom which determines the number of electron that is lost or gained by elements.
F-ion is smaller when compared with O2-ion because of the larger nucleus charge of the F-ion. This is because of the presence of more protons in F-ion that pulls the electrons on the shell’s outside, thus making it smaller.