Increasing Ionization Energy

Question

antimony, phosphorus, arsenic, nitrogen

Arrange in increasing ionization energy

Answer 1

Hi Natalie,

First ionization energy, typically referred to as ionization energy, is the energy it takes to remove the first outer most electron from a neutral element. The lower amount of energy required to remove the first outer most electron means the easier it is to remove it or the more desirable the electron configuration is after the removal. Higher amount of ionization energy means the less desirable the electron configuration is after the removal.

The general trends include decreasing as the energy level increases along a Group (column of the periodic table) because the electrons are further away from the positively charged nucleus (increase in atomic radius) and there are more electrons available. Another general trend is that ionization energy increases as an energy level (row/period of the periodic table) is filled and the element is closer to having a complete octet or valence energy level. There are some dips and spikes related to a full or a half-filled orbital (e.g. Boron dip and beryllium spike). However these dips and spikes are nothing like the peaks and valleys of the Noble Gases (Group 8/8A/VIII) and Alkali Metals (Group 1/I/1A).

For your question, the elements are in the same group so the largest amount of energy to remove the outer most electron will be nitrogen (N) going down to antimony (Sb) as the least in the same order as the Group. Thus it will be Sb, As, P, and N.

Hope that helps!