Molar mass is the mass of one mole of a substance, expressed in g/mol.
H₂O: 2(1.008) + 15.999 = 18.015 g/mol. NaCl: 22.990 + 35.453 = 58.443 g/mol.
This tool is most useful when you need a result you can trust without double-checking. It applies the correct formula automatically and handles edge cases that trip up manual calculation.
The most frequent error is using approximate inputs in a precise calculation and treating the result as if it were exact. The output is only as accurate as the inputs — imprecise measurements or estimated values produce imprecise results.
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Add up the atomic masses of all atoms in the formula. E.g., H₂O = 2(1.008) + 15.999 = 18.015 g/mol.
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