Molecular Geometry and Intermolecular Forces

Flashcards covering key terms and definitions regarding Lewis structures, VSEPR model molecular shapes, and intermolecular forces from Chemistry: The Central Science.

Octet Rule

The principle that atoms tend to gain, lose, or share electrons when forming compounds until they are surrounded by eight valence electrons.

Lewis Symbol

A chemical notation method developed by G. N. Lewis that represents potential bonding electrons using one dot for every valence electron around the element's chemical symbol.

Lone Pairs

Nonbonding electron pairs in a Lewis structure that are located on only one atom rather than shared between atoms.

Bonding Pairs

Shared electron pairs in a Lewis structure that connect atoms, represented by two dots or a single line.

Valence-Shell Electron-Pair Repulsion (VSEPR) Model

A model used to predict molecular geometry, stating that the best spatial arrangement of a given number of electron domains is the one that minimizes repulsions among them.

Electron Domains

The specific directions around a central atom in which electrons point, regardless of whether a domain contains a single bond, multiple bond, or lone pair.

Intramolecular Forces

Strong attractive forces and chemical bonds that hold atoms together within a single molecule.

Intermolecular Forces

Weak forces of attraction existing between different molecules that influence physical properties such as boiling and melting points.

Dispersion Forces

Intermolecular attractions experienced by all atoms and molecules caused by instantaneous, short-lived fluctuations in electron distribution.

Polarizability

The ease or tendency of an atom or molecule's electron cloud to distort, generating a temporary polarity.

Dipole–Dipole Interactions

Intermolecular electrostatic attractions existing between the oppositely charged partial ends ($\delta^+$ and $\delta^-$) of neutral polar molecules.

Hydrogen Bonding

An unusually strong form of dipole–dipole interaction that occurs when a hydrogen atom bonded to a highly electronegative atom ($\text{N}$, $\text{O}$, or $\text{F}$) is attracted to an electronegative atom in a neighboring molecule.

Ion–Dipole Interactions

Attractive forces between an ion and the partial charges on polar molecules, enabling ionic compounds to dissolve in polar solvents.

van der Waals Forces

A general term encompassing intermolecular attractions between neutral molecules, specifically dispersion forces and dipole–dipole forces.