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. This means that Fluorine is the most electronegative element, the element that has the strongest pull on its outer shell electrons and other electrons it encounters while Francium is the weakest electronegative element containing the weakest pull on outer shell electrons.
While the trends and electron configuration go hand-in-hand, electron configuration affects them all in different ways. Whether it causes decreasing or increasing on the periodic table, it results in the trends and...