Which Element Is the Least Electronegative?

Francium has the lowest electronegativity of the elements listed on the Pauling Electronegativity Scale. The Angelo State University website defines electronegativity as an atom's ability to attract the shared electrons found in covalent bonds.

Linus Pauling introduced his electronegativity scale in 1932. He assigned fluorine an electronegativity of 3.98 and scaled the electronegativity values for the other elements accordingly.

In groups — the vertical columns of the periodic table — electronegativity decreases from top to bottom. Francium has an electronegativity of 0.70. The other elements in group 1 have electronegativity values ranging from 0.79 to 2.20.

Electronegativity increases when moving from left to right on Pauling's scale. Radium, the element next to Francium on the scale, has an electronegativity of 0.89. Pauling did not assign an electronegativity for every element.