VOCABULARY TERMS

Absolute zero

The lowest temperature possible

Avogadro’s number

The number of molecules of any gas present in a volume of 22.41 L

Chemical symbol

A one or two-letter designation of an element

Dimensional analysis

The use of a set of units to establish the form of an equation

Distillation

The action of purifying a liquid by a process of heating and cooling

Extensive property

A property that depends on the amount of matter in a sample (Ex:Mass and volume)

Heterogeneous mixture

A mixture in which the composition is not uniform throughout

Homogeneous mixture

A mixture in which the composition is uniform throughout

Intensive property

Properties that do not depend on the amount of the substance (Ex:color, melting point)

Kelvin scale

A unit of measurement for temperature where 0 K is absolute zero

Law of conservation of mass

Mass is neither created nor destroyed in chemical reactions

Mole

The amount of a chemical substance that contains as many elementary entities

Precipitate

The process of transforming a dissolved substance into an insoluble solid from a supersaturated solution

Significant figures

Rules for determining the number of significant figures in a measurement

Atomic absorption spectrum

Detects elements in either liquid or solid samples through characteristic wavelengths of electromagnetic radiation

Atomic emission spectrum

The spectrum of frequencies of electromagnetic radiation emitted due to electron transitions

Atomic number

The charge number of an atomic nucleus

Atomic orbital

A function describing the location and behavior of an electron in an atom

Aufbau principle

Electrons first fill subshells of the lowest available energy

Cathode ray

Streams of electrons observed in discharge tubes