A chemical formula is a short way of writing the chemical symbols and numbers that represent substances, molecules, and compounds in chemistry. These abbreviations consist of a capital letter and often a lower case letter. Each chemical also has a corresponding atomic number and atomic mass that gives us more information about it. This information can be found in the periodic table of elements
A noteworthy subset of chemicals is covalent molecules which are made-up of nonmetal elements (groups 13-17 and hydrogen). Names of covalent compounds must include prefixes that indicate how many atoms of each element are present. Another subset is ionic compounds, which do not use prefixes in naming and which contain metals and nonmetals.