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Chemical Equation calculator
Chemical Equation calculatorChemical Equation
Auto-Balance · Atom Count · Molar Mass Engine
Quick Examples:
H₂+O₂→H₂O
CH₄+O₂→CO₂+H₂O
Fe+O₂→Fe₂O₃
N₂+H₂→NH₃
C₃H₈+O₂→CO₂+H₂O
KMnO₄+HCl
Ca(OH)₂+H₃PO₄
About the Chemical Equation calculator
Balance a chemical equation so that the number of atoms of each element is the same on both sides, as the law of conservation of mass requires.
How to use the Chemical Equation calculator
- Type your equation using an arrow (→ or ->) or an equals sign, for example
H2 + O2 -> H2O. - Press Balance & Analyze to see the balanced equation and the atom count.
Formula and method
Balancing finds whole-number coefficients so that each element has equal atoms on the left and right. Only coefficients can change, never the subscripts inside a formula.
Worked example
H₂ + O₂ → H₂O balances to 2H₂ + O₂ → 2H₂O.
Tips
- Write formulas with correct capitalisation: Co is cobalt, CO is carbon monoxide.
- Balance elements that appear in only one compound first, then hydrogen and oxygen last.
Frequently Asked Questions
Atoms are not created or destroyed in a chemical reaction, so the same numbers must appear on both sides.