Why Does Electronegativity Decrease Down the Periodic Table?

[scott_alexsk]

I have been wondering for the past several weeks why electronegativity continuanually decreases as one goes down the rows, hence the metalollid steps. Is it just that as the shell of an atom expands with the addition of electrons, the proton force becomes weaker and weaker as a result of the greater distance? I suppose that is the most logical assumption since the strong magnetic force is expodentially weaker at longer distances.
-Scott

 

[Gokul43201]

1. There is no such thing as a "strong magnetic" force. The force between the nucleus and the electron is an electrostatic force.

2. The force does not decay exponantially wuth distance. It falls away as the inverse square of the distance.

3. The rest, for the most part, is fine.

 

[ZapperZ]

There is also additional shielding by inner electrons. So the outer electrons, especially if it is a d-orbital electron, do not "see" the full nuclear charge.

Zz.