Science Vocab Crossword

the basic unit of a chemical element.
the central and most important part of an object, movement, or group, forming the basis for its activity and growth.
atomic orbital.
a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron, but of opposite sign.
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
a particle smaller than an atom (e.g., a neutron) or a cluster of such particles (e.g., an alpha particle).
the mass of an atom of a chemical element expressed in atomic mass units.
the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.
the state or power of being reactive or the degree to which a thing is reactive.
the state or power of being reactive or the degree to which a thing is reactive. located on the outer circle of the energy levels.
a table of the chemical elements arranged in order of atomic number, usually in rows, so that elements with similar atomic structure (and hence similar chemical properties) appear in vertical columns.
a chemical symbol is a notation of one or two letters representing a chemical element.
a set of elements occupying a column in the periodic table and having broadly similar properties arising from their similar electronic structure.
a set of elements occupying an entire horizontal row in the periodic table.
a solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity.
an element or substance that is not a metal.
an element (e.g., germanium or silicon) whose properties are intermediate between those of metals and solid nonmetals. they are electrical semiconductors.
any of the gaseous elements helium, neon, argon, krypton, xenon, and radon, occupying group 18 of the periodic table.