Electronegativity

Definition

Electronegativity is a measure of an atom's ability to attract and hold onto electrons within a chemical bond. It is a dimensionless quantity usually assigned values on the Pauling scale.

5 Must Know Facts For Your Next Test

1. Fluorine has the highest electronegativity value of 3.98 on the Pauling scale.
2. Electronegativity generally increases across a period from left to right in the periodic table.
3. Electronegativity generally decreases down a group in the periodic table.
4. Differences in electronegativity between two atoms can predict bond type: nonpolar covalent, polar covalent, or ionic.
5. A large difference in electronegativity between bonding atoms often results in an ionic bond.

Review Questions

• What trend does electronegativity follow across a period and down a group in the periodic table?
• How does electronegativity relate to bond polarity?
• Which element has the highest electronegativity and why?

Related terms

Pauling Scale: A numerical scale used to measure an atom's electronegativity based on bond dissociation energies.

Ionic Bond: A type of chemical bond formed through electrostatic attraction between oppositely charged ions.

Polar Covalent Bond:

A type of covalent bond where electrons are unequally shared between two atoms due to differences in their electronegativities.