ch11_IMF

Intermolecular Forces

The forces of attraction or repulsion between neighboring particles (atoms, molecules, or ions).

Covalent Bonds

Strong intramolecular forces that result from the sharing of electrons between atoms.

Dipole-Dipole Forces

Attractive forces between the positive end of one polar molecule and the negative end of another.

Hydrogen Bonds

A strong type of dipole-dipole interaction that occurs between hydrogen and highly electronegative atoms (N, O, F).

London Dispersion Forces

Weak intermolecular forces from temporary fluctuations in electron density, present in all molecules.

Ion-Dipole Attractions

Strong attractions between an ion and a polar molecule, critical in solutions of ionic compounds.

Polarizability

The ease with which the electron cloud of a molecule can be distorted.

Boiling Point (bp)

The temperature at which the vapor pressure of a liquid equals the atmospheric pressure.

Normal Boiling Point

The boiling point of a liquid at a pressure of 1 atmosphere.

Phase Changes

Transformations from one phase (solid, liquid, gas) to another due to changes in temperature and pressure.

Sublimation

Phase change from solid to gas without passing through the liquid state.

Condensation

The phase change from gas to liquid.

Triple Point

The unique set of conditions at which all three phases (gas, liquid, solid) coexist in equilibrium.

Critical Point

The end point of a phase equilibrium curve; above this point, the liquid and gas phases are indistinguishable.

Surfactants

Substances that have both polar and non-polar characteristics, used to increase solubility.

Equilibrium

The state in which the rate of evaporation equals the rate of condensation.

Phase Diagram

A graph depicting the states of a substance under varying temperature and pressure conditions.

Exothermic Process

A process that releases heat to its surroundings.

Endothermic Process

A process that absorbs heat from its surroundings.

Molar Heat of Fusion (ΔHfus)

The heat absorbed when one mole of solid melts at constant temperature and pressure.

Molar Heat of Vaporization (ΔHvap)

The heat absorbed when one mole of liquid vaporizes at constant temperature and pressure.

Supercritical Fluid

A state of matter above its critical temperature and pressure where it exhibits properties of both liquid and gas.