Stoichiometry Calculator
Calculate stoichiometric ratios, limiting reactants, theoretical yield, actual yield, and percent yield for chemical reactions. Chemistry calculator for high school and university students. Supports balanced equation verification and mole-to-mole conversions.
Stoichiometry Concept
Mol A / Coef A = Mol B / Coef BVariables:
- Mol ANumber of moles of substance A (Known)Number of moles of substance A (Known)
- Coef AReaction coefficient of substance AReaction coefficient of substance A
- Mol BNumber of moles of substance B (Unknown)Number of moles of substance B (Unknown)
- Coef BReaction coefficient of substance BReaction coefficient of substance B
How to Use the KalkuLab Stoichiometry Calculator
- 1
Balance the Reaction
Make sure you have a balanced chemical equation with correct coefficients.
- 2
Enter Substance A Data
Enter the number of moles of the known substance and its coefficient.
- 3
Enter Substance B Coefficient
Enter the coefficient of the substance whose moles you want to find.
- 4
Calculate
The calculated moles of substance B will appear automatically.
Examples
Combustion Reaction
Problem:
Reaction: 2H₂ + O₂ → 2H₂O. If 4 mol of H₂ is available, how many mol of O₂ are needed?
Solution:
- 1.Known substance (H₂): Moles = 4, Coefficient = 2
- 2.Unknown substance (O₂): Coefficient = 1
- 3.Formula: Mol O₂ = (Coeff O₂ / Coeff H₂) × Mol H₂
- 4.Calculate: Mol O₂ = (1 / 2) × 4 = 2 mol
Result:2 mol O₂
2 moles of oxygen are needed to fully react with 4 moles of hydrogen.
Frequently Asked Questions
What is stoichiometry?
Stoichiometry is the branch of chemistry that studies the quantitative relationships between reactants and products in a chemical reaction.
Why must the reaction be balanced?
The Law of Conservation of Mass states that mass is conserved before and after a reaction. A balanced equation ensures the same number of atoms of each element on both sides, making mole ratios accurate.