A molecular formula shows the exact number and types of atoms in a molecule. It uses chemical symbols for the elements and subscript numbers to show how many atoms of each element are present. For example:
The molecular formula of water is H2O, which means that it contains:
2 hydrogen atoms
1 oxygen atom
The molecular formula does not show how the atoms are arranged, it only tells us the total number of each type of atom in the molecule. It is useful in GCSE Chemistry for understanding the composition of substances and comparing with empirical formulas.
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