Which element among elements 2, 4, and 6 has the lowest ionization energy?

Element 6 has the lowest ionization energy

Explanation:

The ionization energy increases across the period but decreases down the group of a periodic table.

Which implies that the elements with the lowest ionization energies would be in the bottom left-hand corner of the periodic table. The change in ionization energies is also increases going down the periodic table (by change within a group) than going across the periodic table (by change within a period). From the 3 elements above we could infer that element 6 has the lowest ionization energy.

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.