Question | Answer |
The average mass of one atom of an element. | atomic mass |
A chart of the elements showing the repeating pattern of their properties. | periodic table |
The central core of an atom containing protons and usually neutrons. | nucleus |
A small, positively charged particle in the nucleus of the atom. | proton |
A small particle in the nucleus of the atom, with no electrical charge. | neutron |
A tiny, negatively charged particle that moves around the nucleus of an atom. | electron |
A unit used to measure the mass of particles in atoms; a proton or neutron has a mass of 1 amu. | atomic mass unit |
The number of protons in the nucleus of an atom. | atomic number |
A one- or two-letter representation of an element. | chemical symbol |
Elements in the same vertical column of the periodic table; also called family. | group |
Elements in the same vertical column of the periodic table; also called group. | family |
A horizontal row of elements in the periodic table. | period |
One of the electrons farthest away from the nucleus of the atom; these electrons are involved in a chemical reaction. | valence electron |
A term used to describe material that can be hammered and rolled into shape. | malleable |
A term used to describe a material that can be pulled out into a wire. | ductile |
A substance that can transmit heat or electricity easily. | conductor |
A characteristic of those metals that are attracted to magnets and can be made into magnets. | magnetic |
The ease and speed in which an element or compound combines with other elements and compounds. | reactivity |
The gradual wearing away of a metal element due to a chemical reaction. | corrosion |
A mixture of two or more metals. | alloy |
An element in Group 1 of the periodic table | alkali metals |
An element in Group 2 of the periodic table. | alkaline earth metals |
An element in Group 3 through 12 of the periodic table. | transition metals |
An element in the first row of the rare earth elements in the periodic table. | lanthanides |
An element in the second row of the rare earth elements in the periodic table | actinides |
An element that lacks most of the properties of metals. | nonmetal |
A molecule composed of two atoms that are the same. | diatomic molecule |
The elements in Group 17 of the periodic table. | halogens |
An element in Group 18 of the periodic table. | noble gas |
An element that has some of the characteristics of metals and some of the characteristics of nonmetals. | metalloid |
An element that can conduct electricity under some conditions. | semiconductor |