Electronegativity Differences and Bond Polarity

Vocabulary flashcards covering key concepts, definitions, and trends related to electronegativity differences, bond polarity, partial charges, and molecular polarity.

Electronegativity

The ability of an atom to attract the shared electrons toward itself when it forms a chemical bond.

Bond Polarity

A property describing how equally or unequally electrons are shared between two bonded atoms.

Nonpolar Covalent Bond

A chemical bond in which electrons are shared equally or almost equally between two atoms.

Polar Covalent Bond

A chemical bond in which electrons are shared unequally between two atoms due to a difference in electronegativity.

Ionic Bond

A bond resulting from a very large electronegativity difference, causing electrons to be strongly attracted toward one atom and commonly described as transferred.

Electronegativity Difference ($\Delta \text{EN}$)

The positive numerical difference between the electronegativity values of two bonded atoms, calculated as $\Delta \text{EN} = |\text{EN}_1 - \text{EN}_2|$.

Partial Charges

Charges represented by the symbol $\delta$ that arise in polar covalent bonds because electrons are shared unequally rather than completely transferred.

Partial Negative Charge ($\delta^-$)

The charge assigned to the atom in a chemical bond with greater electronegativity that attracts shared electrons more strongly.

Partial Positive Charge ($\delta^+$)

The charge assigned to the atom in a chemical bond with lower electronegativity that attracts shared electrons less strongly.

Fluorine (F)

The chemical element that possesses the highest electronegativity among all the elements.

Polar Bond vs. Polar Molecule

The distinction that having polar bonds does not automatically make an entire molecule polar, as molecular geometry can cause individual bond polarities to cancel out (e.g., linear $\text{CO}_2$ is nonpolar overall, while bent $\text{H}_2\text{O}$ is polar).