HMH Florida High School Modern Chemistry- Chapter 5

periodic law

the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements

Periodic Table of Elements

A table that classifies elements by their physical and chemical properties; rows are called periods; columns are called groups;

lanthanide

a member of the rare-earth series of elements, whose atomic numbers range from 58 (cerium) to 71 (lutetium)

Actinides

the 14 elements with atomic numbers from 90 to 103

Mendeleev

Created the first periodic table. Arranged elements by increasing atomic mass

Moseley

Arranged the periodic table according to atomic number instead of mass

alkali metals

Group 1, 1 electron in outer level, very reactive, soft, silver, shiny, low density; Lithium, Sodium, Potassium, Rubidium, Cesium, Francium

alkaline earth metals

the elements in Group 2A of the periodic table

transition elements

elements in groups 3-12

main group elements

the p-block elements together with the s-block elements

Halogens

Contains nonmetals, 7 valence electrons in it's outermost energy level. Very reactive

Sublevel

An atomic orbital, or collection of atomic orbitals, that occupy a principal energy level and are called s, p, d, and f.

atomic radius

one-half the distance between the nuclei of identical atoms that are bonded together

Ion

A charged atom

ionization energy

The amount of energy required to remove an electron from an atom

Ionization

any process that results in the formation of an ion

Cation

A positively charged ion

Anion

A negatively charged ion

valence electrons

Electrons on the outermost energy level of an atom

Electronegativity

A measure of the ability of an atom in a chemical compound to attract electrons