| A | B |
|---|
| Avogadro's number | The number of atoms in the atomic mass of an element, or molecules in the formula mass of a compound |
| chemical bond | an attraction between two or more different atoms that binds them together |
| chemical formula | a representation of a compound that includes the symbols and numbers of atoms in the compound |
| covalent bond | a type of chemical bond that is formed when two atoms share electrons |
| diatomic molecule | a molecule that has only two atoms of the same element |
| energy level | a region around the nucleus of an atom where electrons are most likely to be found; only a certain number of electrons can be found in each energy level of an atom |
| formula mass | determined by adding up the atomic mass units of all the atoms in the compound; a way to compare the masses of molecules of different compounds |
| ionic bond | a type of chemical bond between atoms gained or lost electrons; a bond between ions |
| ion | an atom that has an electrical charge |
| monoatomic ion | ions that contain only one type of atom. |
| octet | an atom’s eight valence electrons. |
| polyatomic ion | ions that contain more than one type of atom |
| polymer | a large molecule that is composed of repeating smaller molecules called subunits or monomers |
| react | describes how atoms interact when forming a chemical bond with another atom. |
| subscript | a number in a chemical formula that show the number of a type of atom. |
| valence electron | the electrons in an atom that are involved in the formation of chemical bonds |
| electronegativity | the attraction an atom has for the shared pair of electrons in a chemical bond. |
| octet rule | states that atoms form bonds with other atoms by sharing or transferring them to complete their octet and become stable |
| ionic compound | a compound that is made up of ions |
| oxidation number | indicates how many electrons are lost or gained (or shared) when bonding occurs |
| covalent compounds | a compound that consists of atoms that are covalently bonded |
| binary compounds | a covalent compound that consists of only two types of elements |
| molecular formula | includes the symbols for and number of atoms of each element in a compound |
| relative mass | a quantity that allows for comparison between amounts of matter that are very small |
| hydrate | a compound that has water molecules chemically bonded to its ions |
| anhydrous | means “without water”; describes the state of a hydrate that has lost water through evaporation |
| mole | one set of 6.02 e23 atoms or molecules |
