Molecular formula
What Molecular formula means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Molecular formula
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Reference: OCR
The actual number of atoms per molecule, found by dividing the relative molecular mass by the empirical formula mass and multiplying the empirical formula by that whole number.
The actual number of atoms of each element in a compound, stating how many atoms of each element are actually present in one molecule.
The number and type of atoms of each element in a molecule, not reduced to the simplest ratio.
Gives the total number of each atom in one molecule, so ethanol is C₂H₆O.
The actual numbers of atoms in a molecule.
Topics that use Molecular formula
- Empirical and molecular formula (AQA A-Level)
- Nomenclature (AQA A-Level)
- Amount of substance (OCR A-Level)
- Basic concepts of organic chemistry (OCR A-Level)
Related terms
- Empirical formula
- Displayed formula
- General formula
- Homologous series
- Alphabetical ordering of substituents
- alphabetical prefixes
- amount of substance
- Aromatic compound
Using Molecular formula in the exam
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