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a gas like state of matter consisting of a mixture of free electrons and atoms that are stripped of there electrons

Nuclear fusion

the process in which two atomic nuclei combine to form a larger nucleus forming a heavier element and releasing a huge amounts of energy


a cloudlike region of gases left over in the remains of a shrinking sunsized star


an explosion of a massive star


an element that lacks most properties of a metal

Diatomic molecule

a molecule consisting of two atoms


an element found in Group 17 of the periodic table

Noble gas

an element found in Group 18 of the periodic table


an element that has some characteristics of both metals and nonmetals


a substance that can conduct electricity under some conditions


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


a term used to describe material that can be pounded into shapes


a term used to describe a material that can be pulled out into a long wire


the ability of an object to transfer heat or electricity to another object


the ease and speed with which an element combines or reacts with other elements and compounds


the gradual wearing away of metal elements due to a chemical reaction

Alkaline earth metal

an element in group 2 of the periodic table

Transition metal

one of the elements on group 3 through 12 of the periodic table


a mixture of two or more elements, one of which is metal

Particle accelerator

a machine that moves atomic nuclei at higher and higher speeds until they crash into one another sometimes forming heavier elements

Atomic mass

the average mass of all the isotope of an element

Periodic table

a chart of the elements showing the repeating pattern of their properties

Chemical symbol

a one or two letter representation of an element


a horizontal row of elements on the periodic table


elements in the same vertical column of the periodic table; also called family


the central core of an atom containing protons and usually neutrons


a small positively charged particle in the nucleus of the atom


a small particle in the nucleus of the atom with no electrical charge


a tiny negatively charged particle the moves around the nucleus of an atom

Atomic number

the number of protons in the nucleus on an atom


an atom with the same number of protons and a different number of neutrons from other atoms of the same element

Mass number

the sum of protons and neutrons in the nucleus of an atom

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