The little numbers in chemistry formulas represent the number of atoms or molecules present in a compound. These numbers are called subscripts and are written as a subscript to the right of the chemical symbol or formula.
For example, in the chemical formula H2O, the subscript 2 indicates that there are two hydrogen (H) atoms bonded to one oxygen (O) atom in a water molecule. Another example is CO2, where the subscript 2 indicates that there are two oxygen (O) atoms bonded to one carbon (C) atom in a carbon dioxide molecule.
The subscripts provide information about the ratios of the atoms or molecules present in a compound. They are essential for accurately representing the composition and structure of chemical compounds. Changing the subscript will change the stoichiometry of the compound, representing a different number of atoms or molecules in the formula.