Atom/Molecular Mass Calculator

This calculator determines the **Molecular Weight (Molar Mass)** of a chemical compound by parsing its formula and summing the atomic masses of all constituent atoms.

The core formula is:

$$ M = \sum_{i} (N_i \cdot A_i) $$

Where:

• $M$ is the Molecular Weight (Molar Mass) in g/mol.
• $N_i$ is the number of atoms for element $i$ in the compound.
• $A_i$ is the standard atomic weight (molar mass) of element $i$ in g/mol.

The **Elemental Percentage by Mass** for any element $X$ is calculated as:

$$ \text{Mass } \% (X) = \frac{N_X \cdot A_X}{M} \times 100 $$

We use the IUPAC Standard Atomic Weights for the calculation.