General Chemistry 2: Intermolecular Forces, Liquids, Solids, Colligative Properties, and Phase Changes

Vocabulary practice flashcards generated from lecture notes covering intermolecular forces, kinetic molecular theory, colligative properties, states of matter, and phase changes.

Intermolecular Forces

Attractive forces that exist between molecules and directly influence their physical properties.

Hydrogen Bonding

A strong type of intermolecular force occurring when hydrogen is directly bonded to highly electronegative atoms, specifically $\text{N}$, $\text{O}$, or $\text{F}$.

Dipole-Dipole Forces

Intermolecular attractions between the positive end ($\delta^+$) of one polar molecule and the negative end ($\delta^-$) of another polar molecule.

London Dispersion Forces

The weakest intermolecular forces, present in all molecules, caused by temporary shifts in electron distribution.

Ion-Dipole Forces

Intermolecular attractions that occur between an ion and a polar molecule, representing the strongest type among intermolecular forces.

Polarizability

The ease with which an electron cloud or dipole can be induced in a molecule, which increases as molecular mass increases.

Intramolecular Forces

Chemical bonds (such as ionic or covalent bonds) that hold atoms together inside a single molecule or compound.

Bond Dipole

A vector representation showing the direction of unequal electron sharing, pointing from the less electronegative atom to the more electronegative atom ($\delta^+ \rightarrow \delta^-$).

Colligative Properties

Properties of solutions that depend exclusively on the number of solute particles present, rather than the chemical identity of the solute.

Electrolytes

Substances that produce ions when dissolved in solution, allowing the resulting solution to conduct electricity.

Van 't Hoff Factor

The ratio ($i$) of the number of particles produced in solution per formula unit of solute dissolved, used to adjust colligative property calculations.

Raoult's Law

The principle stating that the vapor pressure of a solution is directly proportional to the mole fraction of the solvent.

Vapor Pressure Lowering

A colligative property where the vapor pressure of a solvent decreases upon the addition of a non-volatile solute, expressed as $\Delta P = X_{\text{solute}} P^{\circ}_{\text{solvent}}$

Boiling Point Elevation

A colligative property describing the increase in a solvent's boiling point caused by a dissolved non-volatile solute, calculated using $\Delta T_b = i K_b m$.

Freezing Point Depression

A colligative property describing the decrease in a solvent's freezing point caused by a dissolved non-volatile solute, calculated using $\Delta T_f = i K_f m$.

Osmotic Pressure

The pressure required to stop the flow of solvent through a semipermeable membrane into a more concentrated solution, defined by $\pi = iMRT$.

Surface Tension

The elastic property of a liquid's surface that allows it to resist external force due to cohesive interactions between molecules.

Viscosity

A quantitative measure of a liquid's resistance to flow, where stronger intermolecular attractions lead to higher viscosity.

Capillary Action

The movement of a liquid through a narrow space or tube against the force of gravity due to cohesive and adhesive forces.

Unit Cell

The smallest repeating structural unit that displays the complete three-dimensional symmetry and pattern of a crystal.

Crystal Lattice

A continuous three-dimensional network of connected unit cells representing the arrangement of particles in a crystal.

Amorphous Solids

Solids lacking an ordered, repeating internal molecular structure, exhibiting irregular shapes and gradual softening rather than a sharp melting point.

Crystalline Solids

Solids composed of an ordered, repeating three-dimensional arrangement of particles with distinct, sharp melting points.

Metallic Crystals

Crystalline solids composed of metal atoms held by metallic bonds, rendering them malleable, ductile, lustrous, and conductive.

Ionic Crystals

Hard, brittle crystalline solids composed of cations and anions held by ionic bonds, featuring high melting points and conductivity when molten or aqueous.

Molecular Crystals

Crystalline solids held together by intermolecular forces, characterized by soft texture, low melting points, and poor electrical conductivity.

Covalent Crystals

Crystalline solids consisting of atoms linked by an extended continuous network of covalent bonds, characterized by extreme hardness and high melting points.

Polymorphism

The ability of a single chemical substance to exist in more than one crystalline structure while retaining the exact same chemical composition.

Heat of Fusion

The heat energy ($\Delta H_f$) required to transform a given amount of a substance from a solid to a liquid at its melting point.

Heat of Vaporization

The heat energy ($\Delta H_v$) required to transform a given amount of a substance from a liquid to a gas at its boiling point.

Phase Diagram

A graphical plot displaying the physical state of a substance across varying conditions of temperature and pressure.

Triple Point

The specific temperature and pressure conditions at which solid, liquid, and vapor phases coexist in dynamic equilibrium.

Critical Point

The threshold temperature and pressure above which distinct liquid and gas boundaries vanish, forming a supercritical fluid.

Sublimation

The endothermic phase transition in which a substance converts directly from a solid to a gas without entering the liquid phase.

Deposition

The exothermic phase transition in which a substance converts directly from a gas to a solid without entering the liquid phase.

Like Dissolves Like

A fundamental solubility principle stating that polar solvents dissolve polar solutes and nonpolar solvents dissolve nonpolar solutes.