Final answer:
The empirical formula represents the lowest whole-number ratio of elements in a compound and is always the accepted formula when referring to this simplified ratio, which may differ from the actual molecular formula.
Step-by-step explanation:
The empirical formula is always the accepted formula for a compound when it is represented by its lowest whole-number ratio of elements. For instance, the molecular formula for glucose is C6H12O6, but when we simplify it to the lowest whole-number ratio, the empirical formula is CH2O.
In practical applications, determining the empirical formula is a critical first step in the chemical analysis of an unknown compound. If the molecular formula can be reduced to a simpler whole-number ratio, that result is the empirical formula.