Identify the chemical formula.
Determine the number of atoms of each element in the formula.
Find the atomic (molar) mass of each element from a periodic table (units: g/mol).
Multiply each element’s atomic mass by its atom count in the formula.
Add all the resulting products to get the total molar mass.
If the formula includes parentheses or subscripts, multiply the atom counts inside parentheses by the subscript outside.
If the compound is ionic, use the full formula as written (include charge only if needed for naming, not for molar mass).
Report the final sum in g/mol.