Which has the largest radius?

Question

Ne, F-, Na+

Which has the largest and smallest radius?

Does the charge make a difference in radius size?

Answer 1

To answer your 2nd question first, YES, the charge does make a difference in the radius.

Negative ions (anions) are larger because you've added an electron

Positive ions (cations) are smaller because you've removed an electron

Atomic radii increase going from left to right across the periodic table, and they increase within a group going from top to bottom in the table.

Na+ and Ne will have the same electron configuration with both having 10 electrons, but Na⁺ has 11 protons vs Ne with only 10 protons. Thus, Ne will have a larger radius than Na⁺. F^- will be larger yet.

So, the largest is F^- and the smallest is Na⁺