Molecular formula

Definition

A molecular formula indicates the types and numbers of atoms in a molecule of a substance. It shows the actual number of each type of atom present in a single molecule.

5 Must Know Facts For Your Next Test

1. A molecular formula is different from an empirical formula; it gives the exact number of each type of atom, not just the simplest ratio.
2. For example, the molecular formula for glucose is $C_6H_{12}O_6$, while its empirical formula is $CH_2O$.
3. Molecular formulas are essential for understanding the composition and structure of compounds in chemistry.
4. The molecular formula can be derived if both the empirical formula and molar mass are known.
5. This type of chemical formula does not provide information on how atoms are arranged or bonded together.

Review Questions

• What information does a molecular formula provide about a compound?
• How does a molecular formula differ from an empirical formula?
• Why is it important to know both the empirical and molecular formulas of a compound?

Related terms

Empirical Formula:

A chemical formula showing the simplest whole-number ratio of elements in a compound.

Structural Formula:

A chemical formula that shows the arrangement of atoms within a molecule.

Molar Mass:

The mass in grams of one mole of molecules or atoms.