Chemical equation balancer
This chemical equation balancer takes reactants and products separated by an arrow, for example C3H8 + O2 -> CO2 + H2O, and returns the smallest whole-number coefficients with an atom count for each element.
Source: Wikipedia – Reaktionsgleichung (Stöchiometrie, Ausgleichen). Updated: .
How it is calculated
A chemical equation is balanced when each element has the same number of atoms on both sides. C3H8 + O2 → CO2 + H2O becomes C3H8 + 5 O2 → 3 CO2 + 4 H2O.
How the balancing works
Every element gives one equation: atoms on the left minus atoms on the right equals zero. Together they form a linear system whose smallest whole-number solution gives the coefficients. No trial and error and no rounding, because the calculation uses exact fractions.
How to write the formulas
- Element symbols with a capital first letter, numbers right behind: H2O, Fe2O3.
- Brackets are fine: Ca(OH)2, Al2(SO4)3. Water of crystallisation with a dot or star: CuSO4*5H2O.
- Ions with a charge after a caret: Fe^3+, MnO4^-, electrons as e^-.
- Arrow as -> or =, substances separated by +.
Frequently asked questions
How do you balance a chemical equation?
Put whole-number coefficients in front of the formulas until every element has the same number of atoms on both sides. The subscripts inside a formula must never be changed.
Why does the balancer say there are several solutions?
If you put several independent reactions into one equation, infinitely many coefficient sets fit. Split the reactions and the answer is unique.
How do I enter ions and electrons?
Write the charge after ^, such as Fe^3+ or SO4^2-. Electrons are e^-. The total charge is then balanced like an extra element.
Sources and legal basis
- Wikipedia – Reaktionsgleichung (Stöchiometrie, Ausgleichen)
- Wikipedia – Chemical equation (Balancing, Ladungsausgleich)
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