In a chemical formula, what does the subscript indicate?

In a chemical formula, the subscript specifically indicates the number of atoms of an element present in a molecule. For instance, in water (H₂O), the subscript '2' means there are two hydrogen atoms for every one oxygen atom in the molecule. This notation is essential for understanding the composition of a compound, as it conveys the exact ratio of different elements involved. Therefore, when interpreting a chemical formula, the subscripts provide insight into the molecular structure and help in calculating the molar mass of the compound based on the number of atoms of each element represented.