Answer: F, O, N, C, B
Explanation: The element with the greatest electronegativity will have the smallest radius because it holds the electrons closest to the nucleus. Fluorine is the most electronegative element (it is in the upper right of the periodic table), Francium is the lease (it is the lower left of the periodic table). With this knowledge, you should be able to recognize a trend in the periodic table associated with atomic radius size and electronegativity.