A term used to describe material that can be pounded into shapes
A class of elements characterized by physical properties that include shininess, malleability, ductility, and conductivity
The sum of protons and neutrons in the nucleus of an atom
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.
The number of protons in the nucleus of an atom.
A negatively charged particle that is found outside the nucleus of an atom.
A positively charged particle that is part of an atom's nucleus.
The specific amount of energy an electron has.
An atom with the same number of protons and a different number of neutrons from other atoms of the same element.
The central core of the atom.
A horizontal row of elements in the periodic table showing the repeating pattern of their properties
A chart of the elements showing the repeating pattern of their properties.
The basic particle from which all elements are made.
Elements in the same vertical column of the periodic table; also called a family.
A fast-moving electron that is given off as nuclear radiation.
An element in Group 1 of the periodic table.
The gradual wearing away of a metal element due to a chemical reaction.
The ease and speed with which an element combines, or reacts, with other elements and compounds.
A one- or two-letter representation of an element.
The ability of an object to transfer electric current.
A term used to describe a material that can be pulled out into a long wire.
A radioactive isotope that can be followed through the steps of a chemical reaction or industrial process.
A machine that moves atomic nuclei at higher and higher speeds until they crash into one another, sometimes forming heavier elements.
A small particle in the nucleus of the atom, with no electrical charge.
The average mass of all the isotopes of an element.
The ability of an object to transfer heat.
An element that lacks most of the properties of a metal.
The ability of a substance to spontaneously emit radiation; a property of unstable isotopes.
The process in which the atomic nuclei of unstable isotopes release fast-moving particles and energy.
A type of nuclear radiation made of high-energy waves.
A type of nuclear radiation consisting of two protons and two neutrons.
An element found in Group 17 of the periodic table.
An element found in Group 18 of the periodic table.
A material that conducts electric current under some conditions.
Elements that have some properties of metals but also have properties that are typical of nonmetals.
A molecule consisting of two atoms.
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