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Chemistry Calculator
Molecular Weight Calculator
Calculate molecular weight from a chemical formula, including formulas with parentheses.
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Supports simple formulas and parentheses. Hydrates like CuSO4·5H2O are not supported yet.
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Molecular weight is usually reported in grams per mole.
Formula
Add the atomic masses of all atoms in the chemical formula.
Molecular weight = Σ atomic masses
Worked example
For calcium hydroxide, Ca(OH)₂ has 1 calcium, 2 oxygens, and 2 hydrogens:
40.078 + 2(15.999 + 1.008) = 74.092 g/mol