Electronegativity is a measure of how strongly an atom attracts shared electrons toward itself when it is in a chemical bond. In simple terms, it tells you which atom “pulls” harder on the bonding electrons in a molecule.

Core idea

  • Electronegativity describes an atom’s tendency to attract electrons or electron density toward itself in a bond.
  • The higher the electronegativity value, the more strongly that atom pulls on the shared electrons.

Why it matters

  • It helps predict which end of a bond will be slightly negative and which will be slightly positive (bond polarity).
  • It gives insight into whether a bond is more covalent or more ionic in character.

How it’s measured (conceptually)

  • Electronegativity is a relative, dimensionless scale; it is not directly measured but calculated from other data such as bond energies.
  • The most common scale is the Pauling scale, where fluorine is the most electronegative element with a value near 4.0.

Periodic table trend

  • Across a period (left to right), electronegativity generally increases because nuclear charge grows while atoms stay relatively small.
  • Down a group (top to bottom), electronegativity generally decreases because valence electrons are farther from the nucleus and more shielded by inner electrons.

Information gathered from public forums or data available on the internet and portrayed here.