Empirical Formula
The Empirical formula is the lowest whole number ratio of the atoms of the elements in a compound. In this video, we show you how to calculate the empirical formula given the percent composition of a compound. We also talk about how the empirical formula and molecular formula are related. We’ll be covering molecular formulas in more depth in another video.
An empirical formula is a chemical formula that shows the simplest ratio of elements in a compound, rather than the actual number of atoms present. It is determined by analyzing the compound's elemental composition and expressing the results as the lowest whole number ratio of the elements.
For example, the empirical formula for glucose is CH2O, which indicates that for every 1 carbon atom, there are 2 hydrogen atoms and 1 oxygen atom present in the molecule.
Empirical formulas are useful for identifying the basic building blocks of a compound and for predicting its molecular formula, which gives the actual number of atoms in the molecule (in the case of glucose, the molecular formula is 6 times the empirical formula, or C6H12O6).
This video has 3 examples worked in full.
Video: Empirical Formula
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