The chemical formula that shows the actual number of atoms of each element present in a molecule is called?

• A. Molecular formula
• B. Empirical formula
• C. Structural formula
• D. Condensed formula

Answer: (A)

This question tests how different ways of writing formulas convey how many atoms are in a molecule. The molecular formula is the one that lists the exact number of each type of atom in a single molecule, giving the real counts. For example, a molecule with six carbons, twelve hydrogens, and six oxygens is written as C6H12O6, directly reflecting its composition.

In contrast, the empirical formula shows only the smallest whole-number ratio of the elements, which may or may not match the actual counts in a particular molecule. The structural formula shows how the atoms are connected and arranged in the molecule, focusing on bonds and geometry rather than just counts. The condensed formula is a shorthand notation that indicates groups and counts but doesn’t explicitly illustrate how atoms are bonded. Because the question asks for the formula that reveals the exact number of atoms in the molecule, the molecular formula is the best fit.