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Elements and the Periodic Table
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 that moves around the nucleus of an atom.
The number of protons in the nucleus of an atom.
An atom with the same number of protons and a different number of neutrons from other atoms of the same element.
The sum of protons and neutrons in the nucleus of an atom.
The average mass of all the isotopes of an element.
A chart of the elements showing the repeating pattern of their properties.
A one- or two- letter representation of an element.
A horizontal row of elements in the periodic table.
Elements in the same vertical column of the periodic table; also called family.
A aclass 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 a metal element due to its chemical reaction.
An element in Group 1 of the periodic table.
alkaline earth metal
An element in Group 2 of the periodic table.
One of the elements in Groups 3 through 12 of the periodic table.
A mixture of two or more elements one of which is a metal.
A machine that moves atomic nuclei at higher and higher speeds until they crash into one another, sometimes forming heavier elements.
An element that lacks most of the properties of a metal.
A molecule consisting of two atoms.
An element found in Group 17 of the periodic table.
An element 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.