What does the term 'empirical formula' provide information about?

The term 'empirical formula' refers specifically to the simplest whole-number ratio of the different elements present in a compound. It provides key information about the composition of a substance by indicating how the atoms of the various elements are proportioned relative to one another.

For example, in the compound glucose, which has the molecular formula C6H12O6, the empirical formula would be CH2O. This indicates that for every carbon atom, there are two hydrogen atoms and one oxygen atom in the simplest form, regardless of the actual number of atoms in the molecule. The empirical formula thus captures the fundamental relationships between the elements present without detailing the precise arrangement or the actual number of molecules or overall structure of the compound.

In contrast, other options do not align with the definition of an empirical formula. The precise molecular structure pertains to the connectivity and arrangement of atoms, the average molecular weight refers to calculations tied to molar masses, and the total number of molecules refers to quantities in a particular solution—in all these instances, the focus shifts away from the basic elemental ratios that are central to the empirical formula.