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Question
Explain the term molecular formula.
Solution
- Molecular formula of a compound is the formula which indicates the actual number of atoms of the constituent elements in a molecule.
e.g. The molecular formula of benzene is C6H6. - It can be obtained from the experimentally determined values of percent elemental composition and molar mass of that compound.
- Molecular formula can be obtained from the empirical formula if the molar mass is known.
Molecular formula = r × Empirical formula
r = `"Molecular mass"/"Empirical formula mass"`
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