A table of all the known elements ordered by increasing atomic number and arranged in a manner that models the atomic structure of the elements.
Periodic Table
A row in the periodic table that includes elements that have their valence electrons in the same energy level. Also known as a series.
Period
He gave us the Law of Octaves which first showed the periodicity in the behaviors of elements when listed by atomic mass.
John Newlands
The change in energy when an electron is added to a neutral atom to form an anion.
Electron Affinity
A column of the periodic table that includes elements that have similar properties because they have similar electron configurations. Sometimes called a family.
Group
An element of Group 18 on the periodic table. It is nonreactive with a full valence shell.
Noble Gas
An element of Group 17 on the periodic table. It is a highly reactive nonmetal with seven valence electrons. It easily gains an additional electron to make a 1- anion.
Halogen
One of a general group of elements with similar characteristics, such as being solid at room temperature, lustrous, malleable, ductile, and a good conductor of heat and electricity.
Metal
The law that states that the properties of elements vary periodically with their atomic numbers.
Periodic Law
A set of elements typically placed at the bottom of the periodic table that consists of the f-block elements from Period 6.
Lanthanoid Series
Russian chemist that first listed the elements in order of atomic number giving us the first periodic table. He was able to make accurate predictions about the properties of unknown elements at the time.
Dmitri Mendeleev
The measure of the attraction between the nucleus of an atom and shared electrons in chemical bonds.
Electronegativity
An element from the d block of the periodic table. It is a metal that typically has one or two valence electrons that it easily loses to form a 1+ or 2+ cation.
Transition Metal
In general, the radius of an element's cation will be ___ than the radius of a neutral atom of the element.
Smaller
One of a general group of elements with similar characteristics, such as generally being a gas or a soft, crumbly solid at room temperature, and being a poor conductor.
Nonmetal
The distance from the center of an atom's nucleus to its outermost electron.
A compound that contains sulfur, often sulfur combined with one other element.
Sulfide
Author of the modern periodic table. Developed the periodic law.
An element of Group 1 on the periodic table. It is a soft, highly reactive metal that has one valence electron that it easily loses to form a 1+ cation.
Alkali Metal
A compound that contains oxygen, often oxygen combined with one other element.
Oxide
An element of Group 2 on the periodic table. It is a reactive metal, having two valence electrons that it easily loses to form a 2+ cation.
Alkaline-Earth Metal
An element from the f block of the periodic table.
Inner Transition Metal
An element with an atomic number greater than 92, the atomic number of uranium.
Transuranium Element
A set of elements typically placed at the bottom of the periodic table that consists of the f-block elements from Period 7.
Actinoid Series
The amount of energy required to remove an electron from an atom.
Ionization Energy