How does the trend of electronegativity relate to whether an element is a metal or a non-metal?

1 Answer
Mar 6, 2016

Electonegativity increases ACROSS a Period, and decreases DOWN a Group. It follows that metals should be NOT be very electronegative.

Explanation:

Electronegativity is conceived to be the ability of an atom in a chemical bond to polarize electron density towards itself. This is a contrived rather than a measured parameter in that there are various electronegativity scales, of which the Pauling scale is the most famous. On the Pauling scale, the most electronegative atoms, the NON-METALS fluorine, and oxygen, are to the right of the Periodic Table (of course I exclude the Noble Gases in this discussion).

The least electronegative atoms are those metals to the left of the Periodic Table: the alkali and alkaline earth metals, whose electronegativity is so poor that they readily lose electrons to form #M^+# and #M^(2+)# ions.