| A | B |
|---|
| molecule | several particles joined together to form the basic building block of a substance; atoms held together by chemical bonds |
| chemical formula | the use of chemical symbols and numbers to show the makeup of a compound |
| chemical reaction | the joining of different types of atoms to form a compound |
| word equation | a chemical equation in which the chemicals reacting together and the products that are formed are written in words |
| metal oxide | a compound that is produced when a metal reacts with oxygen |
| *closed | used to describe an atom with a completely filled outermost shell |
| *covalent bonc | a chemical bond formed by sharing of electrons between atoms |
| *ionic bond | a chemical bond formed by the electrical attraction between oppositely charged ions |
| *ion | an atom that has gained or lost electrons |
| proportion | a fixed amount |
| *composition | the way in which distinct parts or elements are combined to form a whole |
