Empirical and Molecular Formulae
Empirical and molecular formulae connect experimental composition data with the actual formula of a compound. These pages build from finding the simplest whole-number ratio of atoms through to using relative molecular mass to scale up to the true molecular formula.
Revision Notes
Empirical Formulae
Revise how to convert masses, percentages or combustion data into mole ratios and then into the simplest whole-number formula.
Start revisingMolecular Formulae
Learn how the empirical formula mass and relative molecular mass are used to find the molecular formula of a compound.
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Download, print and revise the key facts of this topic at a glance.
Empirical and Molecular Formulae Map
Edexcel A Level Chemistry · Topic 5 Formulae, Equations and Amounts of Substance · Empirical and Molecular Formulae
The whole section on one A4 page: empirical formulae from masses and percentages, awkward ratios, molecular formulae and combustion analysis.
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Empirical and Molecular Formulae – Edexcel A Level Chemistry
The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 5. Ideas from this topic are applied across quantitative chemistry, practical work and later physical, inorganic and organic topics.
Chemical Language and Formulae
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