Stoichiometry Calculator
Enter your vacation details to calculate your accrued days and remaining balance
* This calculator provides estimates based on common accrual methods. Company policies may vary. Always verify with your HR department for exact calculations.
What is Stoichiometry?
Stoichiometry is the calculation of the quantities of reactants and products in chemical reactions. It is based on the law of conservation of mass, which states that matter cannot be created or destroyed in a chemical reaction. Stoichiometry allows chemists to predict how much product will form in a reaction or how much reactant is needed to produce a desired amount of product.
Key Concepts in Stoichiometry
Balanced Chemical Equations
A balanced chemical equation shows equal numbers of each type of atom on both sides of the equation. This is the foundation of stoichiometric calculations, as it establishes the ratio of reactants and products.
Mole Concept
The mole is the SI unit for amount of substance. One mole of any substance contains Avogadro's number (6.022 × 10²³) of particles. The mole allows chemists to convert between mass, volume, and number of particles.
Molar Mass
The molar mass of a substance is the mass of one mole of that substance, usually expressed in grams per mole (g/mol). It is calculated by adding the atomic masses of all atoms in a molecule.
Stoichiometric Coefficients
The coefficients in a balanced chemical equation represent the relative number of moles of each substance involved in the reaction. These coefficients establish the stoichiometric ratios used in calculations.
Limiting Reagent
The limiting reagent is the reactant that is completely consumed in a reaction and determines the maximum amount of product that can be formed. Other reactants present in excess amounts will partially remain unreacted.
How to Use the Stoichiometry Calculator
- Enter the chemical equation in the input field (e.g., "H2 + O2 = H2O")
- Click "Balance Equation" to automatically balance the equation
- Select the substance you know the quantity of (the "given" substance)
- Enter the amount and select the appropriate unit (grams, moles, or molecules)
- Select the substance you want to find the quantity of (the "unknown" substance)
- Choose the desired output unit
- Click "Calculate" to perform the stoichiometric calculation
Common Stoichiometry Problems
Mass-to-Mass Calculations
Converting from the mass of one substance to the mass of another substance in a chemical reaction. This is the most common type of stoichiometry problem.
Limiting Reagent Problems
Determining which reactant will be completely consumed first and calculating the amount of product formed.
Percent Yield Calculations
Comparing the actual yield of a reaction to the theoretical yield calculated from stoichiometry.
Solution Stoichiometry
Calculating concentrations, volumes, or amounts of substances in solution-based reactions.
Tips for Accurate Stoichiometric Calculations
- Always start with a balanced chemical equation
- Use the correct molar masses for all substances
- Pay attention to units and perform appropriate conversions
- Identify the limiting reagent when multiple reactants are involved
- Remember that real-world reactions rarely achieve 100% yield
- Double-check your calculations by working backward from your answer