Empirical is derived from a Greek word meaning experienced, and empirical formulas are determined from experimental values. The empirical or simplest formula uses element symbols and subscripts that represent the smallest whole number ratio of atoms in a compound not the actual number of atoms. Empirical formula represents both ionic and molecular compounds. For an ionic compound the empirical formula is also called the formula unit and represents the ratio of ions. For example, KCl has an equal number of potassium and chlorine ions.Barium chloride, BaCl₂ has twice as many chlorine ions as barium. Molecular formulas represent compounds that exist as molecules. The formula C₂ H ₄ has two atoms of carbon and four atoms of hydrogen. The empirical formula is the smallest whole number ratio and would be CH₂.The empirical formula can be determined through analysis and the molecular formula can be calculated from...