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Chemistry TutorMOHAMMAD ABUSAIF
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CHEMISTRY · CALCULATE · UNDERSTAND

Stoichiometry Calculator

Balances a neutral molecular equation with exact integer arithmetic, then converts one known mass or amount into another species using coefficient ratios.

Introductory chemistry

Enter your values

Use a decimal point or scientific notation (1e-3). Choose units before calculating.

Use -> or →. Leading student coefficients are ignored and recalculated.
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Calculations run on your device. No account, name or email is required.

Your result

Enter your values and press Calculate to see your answer and all five solution steps.

n(destination) = n(source) × coefficient(destination) / coefficient(source)

Common Mistakes

  • Do not change subscripts to balance an equation; change coefficients only.
  • A coefficient ratio relates moles, not grams directly. Convert mass through molar mass first.
  • One supplied amount cannot identify a limiting reagent or an actual yield.

Assumptions and limitations

  • Supported scope: up to 12 neutral molecular species and 12 elements; parentheses and Unicode subscripts are accepted. Ionic charges, hydrates, isotope notation, redox-electron balancing, equilibrium arrows, and energy balances are rejected.
  • The balancer ignores typed leading coefficients, then returns the smallest positive whole-number ratio or a clear error for an impossible or underdetermined system.

n(destination) = n(source) × coefficient(destination) / coefficient(source)

Learn More

Connect the calculation to your chemistry course and try a related tool.

Molar Mass CalculatorMole CalculatorPercent Composition CalculatorCourse guides and free testsUniversity chemistry tutoring
Scientific references

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