3875243
Trends with Electron Configuration The electron configuration of an element dictates the element's properties in a chemical reaction. Elements' electron configurations vary regularly along the periodic table. When dealing with the atomic radius, the size decreases going across of the table and increase going down the table. Moving down the atom, electrons are added to the atom, but each time the number of shells increases. Thus the atomic radii will go on increasing. When moving across, electrons are added along a period, they are added to the same shell so the radius doesn't increase. The nuclear force is acting on more electrons, and therefore the electrons keep getting closer to the nucleus, hence the radius decreases. This is because the core charge gradually increases since there is a stronger force of attraction between the valence electrons and the nucleus. Across a period the Ionization Energy increases because the atomic radii and strength of the attractions between electrons and nuclear protons increase, as does the electronic configuration as the number of electrons increase. Down to a group the electronic configuration increases but the Ionization energy decreases because the attraction forces of nucleus and electrons decrease with the increase in atomic radii down to a group. With the exception of the elements that are Noble Gases, electronegativity generally increases from left to right across the periodic table and also increases up the columns.
