Electronegativity

Electronegativity, symbol χ, is a chemical property that says how well an atom can attract electrons towards itself.^[1] The electronegativity of an atom is influenced by the atom's atomic number and the distance between the atom's valence electrons (the outermost electrons that take part in chemical bonding) and its nucleus. It was first theorised by Linus Pauling in 1932 as part of his valence bond theory,^[2] and is related to other chemical properties. Generally, electronegativity increases from the bottom-left to the upper-right of the periodic table; this is known as a periodic trend.

There are many ways to calculate the electronegativity of an atom. The most common way of calculation is the one suggested by Linus Pauling, and it gives the relative Pauling scale. This scale gives elements dimensionless quantities (values) between 0.7 and 3.98, with hydrogen being at 2.20.

The opposite of electronegativity is electropositivity; the measure of how well an atom gives away electrons.

1. ↑ "Electronegativity.", IUPAC Compendium of Chemical Terminology
2. ↑ Pauling, L. (1932). "The nature of the chemical bond. IV. The energy of single bonds and the relative electronegativity of atoms". Journal of the American Chemical Society. 54 (9): 3570–3582. doi:10.1021/ja01348a011.