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Formulas have helped us understand the compound structure and its behavior by letting us know the exact composition of a molecule.
Different atoms have different properties, also, a different arrangement of atoms lead to different geometrical shapes. To understand compound structure and behavior it is necessary to know which atoms are in the molecule and how are they arranged. These two pieces of information can be obtained from the Chemical Formula, which tells us precisely the atoms and the proportions of each one in a given compound.
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