Chemistry: Unit 1 Vocab

The periodic law states that the physical and chemical properties of elements are periodic functions of their atomic

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Period

A horizontal row of elements in the Periodic Table. Elements show trends in properties across a period.

Group

a vertical column in the periodic table that contains elements having similar physical and chemical properties

Metal

A class of elements characterized by physical properties that include shininess, malleability, ductility, and conductivity.

Nonmetal

an element that is a poor conductor of heat and electricity

metalloid (semimetal)

an element with properties between those of metals and nonmetals

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

metallic elements in group 2 of the periodic table which are harder than the alkali metals and are also less reactive

transition metals

Groups 3-12, 1-2 electrons in the outer energy level, less reactive than alsali-earth metals, shiny, good conductor of thermal energy and electrical current, high density

Halogens

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

noble gases

The elements in group 8A of the periodic table.-Colorless-Odorless-Extremely NONREACTIVE

Octect

states that atoms lose, gain, or share electrons in order to acquire a full set of eight valence electrons (the stable electron configuration of a noble gas)

Atomic Radius

one-half the distance between the nuclei of two atoms of the same element when the atoms are joined

ionic radius

Distance from the center of an ion's nucleus to its outermost electron

ionization energy

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

Electronegativity

the ability of an atom to attract electrons when the atom is in a compound