Ch 9/10 - Bonding and Structure

Bond Energy

amount of energy needed to break apart one mole of molecules into its component atoms; used to measure the strength of a chemical bond; bond enthalpy/strength

Delocalized Electrons

can be placed on one atom, but can also be shared between that atom and a neighboring atom; participates in resonance and not limited to one bond

Localized Electrons

electrons that belong to only one atom or bond

Diamagnetism

not attracted to a magnetic field, paired electrons

Paramagnetism

attracted to a magnetic field, unpaired electrons

Dipole Moment

represents the strength of a dipole (equal and opposite charges); based on the product of the charges and their distance

Electronegativity

measure of the tendency of an atom to attract electrons in a covalent bond

Formal Charge

the charge of an atom in a molecule calculated by the difference between the number of valence electrons (as a solitary atom) and the number of bonded and lone pair electrons (in the molecule)

Hybrid Orbitals

concept of mixing/overlapping atomic orbitals (across different atoms in a molecule) to create molecular orbitals

Ionic Bond

type of bond where oppositely charged ions exchange electrons; give/receive e-

Nonpolar Covalent Bond

a type of bond where electrons are shared equally between two atoms with similar electronegativities.

Polar Covalent Bond

a type of bond where electrons are shared unequally between two atoms with different electronegativities

Lattice Energy

the amount of energy required to separate one mole of an ionic compound (gaseous) into its component ions

Pi Bonds

pi bonds involve the lateral/side-by-side overlapping of atomic orbitals; type of covalent bonding; double, triple

Sigma Bonds

sigma bonds are formed through the head-to-head overlapping of atomic orbitals; type of covalent bonding; single, double, triple

Resonance

concept that delocalized electrons can allow a molecule to have multiple correct Lewis structures

VSEPR

Valence Shell Electron Pair Repulsion; model used to predict the geometry of individual molecules based on the electron pairs on the central atom; predicts geometry based on the idea that electrons repel each other and that electron configuration aims to minimize repulsion; lone-lone > lone-bond > bond-bond