CHEMISTRY II

Solids

Solids

Matter with a definite shape and volume.

Amorphous

Solids with no arranged structure of molecules.

Crystalline

Solids with molecules arranged into patterns.

Liquids

Matter with a definite volume but no definite shape.

Surface Tension

The cohesive force at the surface of a liquid.

Viscosity

A measure of a liquid's resistance to flow.

Vapor Pressure

The pressure exerted by a vapor in equilibrium with its liquid.

Boiling Point

The temperature at which a liquid turns to vapor.

Heat of Vaporization

The amount of energy required to convert a liquid into a gas.

Intermolecular Forces of Attraction

Forces that hold molecules together.

Dipole-Dipole

Attraction between polar molecules with partial positive and negative charges.

Hydrogen Bond

A strong type of dipole-dipole interaction involving hydrogen and electronegative atoms (N, O, F).

Ion-Dipole

Interaction between an ion and a polar molecule.

London Dispersion Force

Weak attraction between all atoms and molecules, significant in nonpolar substances.

Expanding the Solvent

Overcoming intermolecular forces in the solvent to accommodate solute.

Expanding the Solute

Separating solute into individual components for interaction with solvent.

Enthalpy of Solution

The total heat change during the dissolution process.

Endothermic

A process that absorbs heat (positive enthalpy change).

Exothermic

A process that releases heat (negative enthalpy change).

Percent by Mass

A calculation of solute mass relative to the total mass of the solution.

Percent by Volume

A calculation of solute volume relative to the total volume of the solution.

Mass-Volume Percent

A calculation of solute mass relative to the solution volume.

Molarity (M)

The number of moles of solute per liter of solution.

Molality (m)

The number of moles of solute per kilogram of solvent.

1st Law of Thermodynamics

Energy cannot be created or destroyed, only transformed.

Open System

A system where matter and energy can freely exchange with surroundings.

Closed System

A system where energy can exchange but matter cannot.

Isolated System

A system where neither energy nor matter can exchange with surroundings.

Conduction

Heat transfer through direct contact.

Convection

Heat transfer through fluid movement.

Radiation

Heat transfer through electromagnetic waves.

Important Elements

Nitrogen (N2), Oxygen (O2), Fluorine (F2), Chlorine (Cl2), Bromine (Br2), Iodine (I2), Hydrogen (H2).

Sulfate

SO4-2, a polyatomic ion.

Ammonium

NH4+, a positively charged polyatomic ion.

Aluminum

Al+3, a cation.

Phosphorus

P-3, an anion.

Carbonate

CO3^2-, a polyatomic ion.

Nitrate

NO3-, a polyatomic ion.

Hydroxide

OH-, a polyatomic ion.

Hydrochloric Acid

HCl-1, a strong acid.

Sulfuric Acid

H2SO4+6, a strong acid.

Carbon

C+4, an element with a +4 oxidation state.