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Pauling Electronegativity values

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Physical Chemistry - Pauling Electronegativity Values


Electronegativity describes the tendency of atoms to gain electrons forming negative ions.  The halogens ..Periodic Table Group VIIA(col 17): are typical electronegative ions.. Considering the hydrogen chloride molecule the chlorine atom is more electronegative than the hydrogen atom and consequently the molecule is polar.  The chlorine atom has a negative charge.

The most common method of assigning values to this property is to use the Pauling scale.  This is based on the bond dissociation energies for which fluorine, the most electronegative element, is given a value 4

Electronegativity in atomic bonds

The electronegativity to can be used to estimate whether a given bond will be nonpolar covalent, polar covalent, or ionic.   It is expected that the electronegativity of an atom in a molecule to be related to its ionization energy and electron affinity, which are properties of isolated atoms.

It is possible to use the difference in electronegativity between two atoms to gauge the polarity of the bonding between them.   The greater difference in electronegativity, the more polar the bond.   Compounds with an electronegativity (EN) difference δEN > 1.7 are generally classified as ionic; those with δEN < 1.7 are covalent.

Table of Pauling Electronegativity Values

Element E. Value  ElementE. Value  ElementE. Value  ElementE.Value
Group(1) IA
Hydrogen 2,20  Lithium0,98  Sodium0,93  Potassium0,82
Rubidium 0,82 Ceasium0,79 Francium0,70 --
Group(2) IIA
Beryllium 1,57 Magnesium1,31 Calcium1,00 Strontium0,95
Barium 0,89 Radium0,90 -- --
Group(3) IIIB
Scandium 1,36 Yttrium1,22 Lanthanum1,10 Actinium1,10
Group(4) IVB
Titanium 1.54 Zirconium1.33 Hafnium1.30 --
Group(5) VB
Vanadium 1.63 Niobium1.60 Tatalum1.50 Dumnium-
Group(6) VIB
Chromium 1.66 Molybdenum2,16 Tungsten2,36 Seaborgium-
Group(7) VIIB
Manganese 1.55 Technetium1,90 Rhenium1,90 Bhorium-
Group(8) VIIIB
Iron 1.83 Ruthenium2,20 Osmium2,20 Hassium-
Group(9) VIIIB
Cobalt 1.88 Rhodium2,28 Iridium2,20 Meitnerium-
Group(10) VIIIB
Nickel 1.91 Palladium2,20 Platinum2,28 Ununnilion-
Group(11) IB
Copper 1.90 Silver1,93 Gold2,54 Unununion-
Group(12) IIB
Zinc1.65 Cadmium1,69 Mercury2,00 Ununbion-
Group(13) IIIA
Boron2,04 Aluminium1,61 Gallium1,81 Indium1,78
Thallium2,04 UuT- -- --
Group(14) IVA
Carbon2,55 Silicon1,90 Germanium2,01 Tin1,96
Lead2,33 -- -- --
Group(15) VA
Nitrogen3.04 Phosphorus2,19 Arsenic2,18 Antimony2,05
Bismuth2,02 UuT- -- --
Group(16) VIA
Oxygen3.44 Sulphur2,58 Selenium2,55 Terrulium2,10
Polonium2,00 Uuh- -- --
Group(17) VIIA
Flourine3.98 Chlorine3,16 Bromine2,96 Iodine2,66
Astatine2,20 Uus- -- --
Group(18) VIIIA
Helium- Neon- Argon- Krypton-
Xenon - Radon- -- --
Chemistry Sites..
  1. ChemWiki-Pauling Electronegativity values... A short article - A good intro
  2. Electonegativity.... Set of very clear notes. Comprehensive but not too detailed..
  3. An Intro'n to the Electronic Structure of Atoms and Molecules.... Notes on molecular bonding
  4. Wikipedia Electonegativities tables....Lots of detailed reference information