Compound - a distinct substance that is composed of the atoms of two or more elements and always contains exactly the same relative masses of those elements; it always contains the same relative numbers of atoms of each element
Chemical Formula - expresses the types of atoms and the number of each type in each unit; atoms are indicated by the element symbols and the number of each type of atom is indicated by the subscript, a number that appears to the right of and below the symbol for the element
Chemical Formula - expresses the types of atoms and the number of each type in each unit; atoms are indicated by the element symbols and the number of each type of atom is indicated by the subscript, a number that appears to the right of and below the symbol for the element