Respuesta :
I believe the correct factor concerning ionization energy within a period would be that the valence electrons essentially remain at about the same distance from the atomic nucleus when moving from left to right on the periodic table. This is because the Atomic number increases by a value of 1, and depending whether or not the maximum number of electrons are found within the shell, it may have another shell or not.
Answer: The attractive force of the nucleus increases.
Explanation:
Ionization energy is the energy required to remove the most loosely bound electron from an isolated gaseous atom.
In a period, the ionization energy increases as we move across a period as the size decreases. The electrons get added to the same shell and the nuclear charge increases.The valence shell moves nearer to the nucleus.
Thus the valence electron gets tightly held by the nucleus due to attractive forces of the nucleus and thus more energy is required to remove the valence electron.