Define empirical and molecular formulas.

Empirical formulas show the simplest ratio of atoms in a compound, while molecular formulas show the actual number of atoms.

Empirical formulas represent the simplest whole-number ratio of atoms in a compound. For example, the empirical formula of glucose is CH2O, which means for every carbon atom, there are two hydrogen atoms and one oxygen atom. It doesn't provide information about the actual number of atoms in a molecule, but it does give the simplest, most reduced ratio of elements within the compound. This formula is particularly useful in chemistry when you want to identify patterns and relationships between different compounds.

On the other hand, molecular formulas show the actual number of each type of atom in a molecule of the compound. Using the previous example, the molecular formula of glucose is C6H12O6. This means a molecule of glucose contains six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. The molecular formula provides more specific information about the compound, including its molecular weight.

It's important to note that while the molecular formula of a compound can be the same as its empirical formula, this isn't always the case. For instance, the empirical formula for hydrogen peroxide is HO, but its molecular formula is H2O2. This is because the molecular formula represents the actual number of atoms, while the empirical formula represents the simplest ratio of atoms.

In summary, both empirical and molecular formulas provide crucial information about a compound. The empirical formula gives the simplest ratio of atoms, which can help identify patterns and relationships between compounds. The molecular formula, however, provides a more detailed view, showing the actual number of each type of atom in a molecule. Both are essential tools in the study of chemistry.

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