Which type of chemical formula represents the most basic structure?

The most basic structure is represented by the empirical formula. An empirical formula gives the simplest whole-number ratio of atoms in a compound, effectively summarizing the composition of the substance without detailing how the atoms are arranged or bonded.

In contrast, molecular formulas provide the actual number of each type of atom in a molecule, but they do not show how those atoms are connected. Lewis dot structures illustrate the arrangement of valence electrons around atoms, while structural formulas give a more detailed representation of how atoms are bonded and the arrangement of the molecule. The empirical formula is therefore the foundational representation because it lays out the simplest form of the chemical composition without the complexity of molecular or structural arrangements.