The relative ability of an atom to draw electrons in a bond toward itself is called the electronegativity of the atom. Atoms with large electronegativities (such as F and O) attract the electrons in a bond better than those that have small electronegativities (such as Na and Mg). The electronegativities of the main group elements are given in the figure below.

When the magnitude of the electronegativities of the main group elements is added to the periodic table as a third axis, we get the results shown in the figure below.

There are several clear patterns in the data in the above two figures.

• Electronegativity increases in a regular fashion from left to right across a row of the periodic table.
• Electronegativity decreases down a column of the periodic table.

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