How to Calculate Molecular Formula
What is Molecular Formula?
The molecular formula gives the actual number of each type of atom in a single molecule of a compound. It is a whole-number multiple (n) of the empirical formula, where n = Molar mass / Empirical formula mass.
Step-by-Step Guide
- 1Determine the empirical formula and its formula mass
- 2Measure or look up the actual molar mass
- 3n = Actual molar mass / Empirical formula mass
- 4Molecular formula = empirical formula × n
Worked Examples
Input
Empirical CH₂O (mass 30) · Actual molar mass 180
Result
n=6 → Molecular formula C₆H₁₂O₆ (glucose)
180/30=6
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