What type of formula shows the arrangement of the atoms in a compound?

The structural formula is the correct answer because it provides a visual representation of how the atoms in a molecule are arranged and bonded to each other. This includes details about the connectivity between atoms, as well as the geometric arrangement of the atoms in space. Unlike a molecular formula, which only indicates the number of each type of atom in the compound (for example, C2H6 for ethane), the structural formula shows how those atoms are connected and can reveal information about the molecule's shape, functional groups, and overall reactivity.

Understanding the structural formula is essential in fields like chemistry and biochemistry, as it allows individuals to infer how a molecule might behave in different chemical reactions or interactions. This level of detail is not provided by empirical formulas, which only represent the simplest whole-number ratio of atoms, or molecular formulas, which summarize the types and amounts of atoms present without detailing their arrangement. The term "summation formula" is not commonly used in this context and does not refer to a specific type of chemical formula.