The simplest whole number ratio of the atoms of each element in a compound is commonly known as the empirical formula. The term empirical refers to the process of elemental analysis, a technique used to determine the relative amounts of each element in a chemical compound. The empirical formula of a compound can be calculated if a compound can be synthesized from its elements. There are three steps required in order to calculate the empirical formula of a given compound. First, the mass of each element in the compound must be determined. Then, the number of moles of each element in the sample must be calculated. Finally, the molar ratio of each element as the smallest whole number must be expressed, yielding the compounds empirical formula.
To determine the empirical formula of a compound (magnesium oxide).