Answer:
Atomic number
Explanation:
Hope it helps you in your learning process.
The electric field produced by a large flat plate with uniform charge density on its surface can be found by using Gauss law, and it is equal to

where

is the charge density

is the vacuum permittivity
We see that the intensity of the electric field does not depend on the distance from the plate. Therefore, the strenght of the electric field at 4 cm from the plate is equal to the strength of the electric field at 2 cm from the plate:
Ionization energy, according to <span>chem.libretexts.org,</span><span> is the quantity of </span>energy<span> that an isolated, gaseous atom in the ground electronic state must absorb to discharge an electron, resulting in a cation. This </span>energy<span> is usually expressed in kJ/mol, or the amount of </span>energy<span> it takes for all the atoms in a mole to lose one electron each.</span>