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Molecular Mass Formula
The molecular mass of a compound is the sum of the atomic masses of all the atoms in a molecule. It is calculated by adding up the atomic masses of all the atoms in the chemical formula.

Formula:
- The molecular mass (M) of a compound is calculated using the formula:
M = (m1 * n1) + (m2 * n2) + (m3 * n3) + ...

Where:
- M is the molecular mass
- m1, m2, m3, etc. are the atomic masses of the elements in the compound
- n1, n2, n3, etc. are the number of atoms of each element in the compound

Example:
- For example, let's calculate the molecular mass of water (H2O):
- Atomic mass of hydrogen (H) = 1
- Atomic mass of oxygen (O) = 16
- Number of hydrogen atoms = 2
- Number of oxygen atoms = 1
- Molecular mass of water (H2O) = (1 * 2) + (16 * 1) = 18

Importance:
- Calculating the molecular mass of a compound is important in determining its properties and reactions. It helps in identifying the composition of the compound and predicting its behavior in chemical reactions.

Conclusion:
- The molecular mass formula is a simple yet crucial calculation in chemistry that helps in understanding the structure and properties of compounds. It is an essential concept for students and professionals in the field of chemistry.