Molecular Formula
Definition and meaning of Molecular Formula in chemistry.
A molecular formula is a chemical formula that specifically indicates the exact number and type of atoms present in a single molecule of a substance. It provides a precise atomic inventory of the atoms that make up a discrete covalent molecule.
In more detail
Unlike an empirical formula, which only shows the simplest whole number ratio of elements in a compound, the molecular formula reveals the actual, true atomic composition of the entire molecule. For example, the empirical formula of benzene is CH, but its full molecular formula is C6H6. To determine a molecular formula experimentally, one typically needs to know both the empirical formula and the accurate molar mass of the compound. It is a vital piece of information for drawing structural formulas and understanding chemical reactivity.
Key facts
| Field | General Chemistry |
|---|---|
| Type | Chemical formula |
| Contrast | Empirical formula |
The molecular formula for glucose is C6H12O6, showing that one single molecule contains exactly 6 carbon, 12 hydrogen, and 6 oxygen atoms.
Frequently asked questions
Can a molecular formula and an empirical formula be the exact same?
Yes. For example, water (H2O) cannot be simplified any further, so its molecular and empirical formulas are identical.