Balancing Formulas Calculator

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Balanced equation
4Fe + 3O2 → 2Fe2O3
Stoichiometry Calculator
Worked out from OpenStax Chemistry 2e, section 4.3 Reaction Stoichiometry and 2 other sources.
Yields assume the written reaction goes to completion with pure reactants and no competing reaction. Confirm the reaction, purity and product basis before relying on the figure for laboratory or process work.

How this is worked out

2 steps
  1. Balanced equation: 4Fe + 3O2 → 2Fe2O3
  2. Molar masses (IUPAC 2021 abridged, dataset ciaaw-2024-abridged + nist-awic-ame2020): M(Fe) = 55.845 g/mol; M(O2) = 31.998 g/mol; M(Fe2O3) = 159.687 g/mol
Stoichiometric coefficientstable
4, 3, 2
Reactantstable
formulacoefficientmolarMass
Fe455.845
O2331.998
Productstable
formulacoefficientmolarMass
Fe2O32159.687

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