Question

from which atom is it easiest to remove an electron? (lowest ionization energy)
f
li
be
n

Explanation:

Ionization energy increases across a period and decreases down a group in the periodic table. Fluorine (F) is a highly electronegative element with a high ionization energy. Beryllium (Be) and Nitrogen (N) are in the second - period and have relatively high ionization energies compared to a much larger and more metallic element. Uranium (U) is a large, heavy metal. Metals generally have lower ionization energies as they tend to lose electrons easily. Among these elements, U has the lowest ionization energy and it is easiest to remove an electron from it.

Answer:

U