Chem Equation Calculator

Theoretical Yield Calculator

Use this calculator to determine the theoretical yield of a product in a chemical reaction, given the mass of a reactant and the balanced chemical equation's stoichiometric coefficients and molar masses.

function calculateTheoreticalYield() { var reactantMass = parseFloat(document.getElementById('reactantMass').value); var reactantMolarMass = parseFloat(document.getElementById('reactantMolarMass').value); var reactantCoefficient = parseFloat(document.getElementById('reactantCoefficient').value); var productMolarMass = parseFloat(document.getElementById('productMolarMass').value); var productCoefficient = parseFloat(document.getElementById('productCoefficient').value); var resultDiv = document.getElementById('result'); resultDiv.innerHTML = "; // Clear previous results if (isNaN(reactantMass) || isNaN(reactantMolarMass) || isNaN(reactantCoefficient) || isNaN(productMolarMass) || isNaN(productCoefficient)) { resultDiv.innerHTML = 'Please enter valid numbers for all fields.'; return; } if (reactantMass <= 0 || reactantMolarMass <= 0 || reactantCoefficient <= 0 || productMolarMass <= 0 || productCoefficient <= 0) { resultDiv.innerHTML = 'All input values must be positive.'; return; } // Step 1: Calculate moles of reactant var molesReactant = reactantMass / reactantMolarMass; // Step 2: Use mole ratio to find moles of product // Moles of product = (Moles of reactant / Reactant Coefficient) * Product Coefficient var molesProduct = (molesReactant / reactantCoefficient) * productCoefficient; // Step 3: Calculate theoretical yield (mass) of product var theoreticalYield = molesProduct * productMolarMass; resultDiv.innerHTML = '

Calculation Details:

'; resultDiv.innerHTML += 'Moles of Reactant = ' + reactantMass.toFixed(3) + ' g / ' + reactantMolarMass.toFixed(3) + ' g/mol = ' + molesReactant.toFixed(4) + ' mol'; resultDiv.innerHTML += 'Moles of Product = (' + molesReactant.toFixed(4) + ' mol / ' + reactantCoefficient.toFixed(0) + ') * ' + productCoefficient.toFixed(0) + ' = ' + molesProduct.toFixed(4) + ' mol'; resultDiv.innerHTML += 'Theoretical Yield of Product = ' + molesProduct.toFixed(4) + ' mol * ' + productMolarMass.toFixed(3) + ' g/mol = ' + theoreticalYield.toFixed(3) + ' g'; }

Understanding Theoretical Yield in Chemical Reactions

In chemistry, a balanced chemical equation provides a quantitative relationship between reactants and products. Stoichiometry is the branch of chemistry that deals with the quantitative relationships between reactants and products in chemical reactions. The "theoretical yield" is the maximum amount of product that can be formed from a given amount of reactants, assuming the reaction goes to completion with 100% efficiency and no losses.

Key Concepts:

• Molar Mass (g/mol): The mass of one mole of a substance. It's calculated by summing the atomic masses of all atoms in a molecule. For example, the molar mass of H₂O is approximately 18.015 g/mol (1.008 g/mol for H * 2 + 15.999 g/mol for O).
• Moles (mol): A unit of measurement for the amount of substance. One mole contains approximately 6.022 x 10²³ particles (Avogadro's number). The number of moles can be calculated by dividing the mass of a substance by its molar mass (Moles = Mass / Molar Mass).
• Stoichiometric Coefficient: The number placed in front of a chemical formula in a balanced chemical equation. These coefficients represent the relative number of moles (or molecules) of each reactant and product involved in the reaction. For example, in 2 H₂ + O₂ → 2 H₂O, the coefficient for H₂ is 2, for O₂ is 1, and for H₂O is 2.

How to Calculate Theoretical Yield:

The calculation of theoretical yield typically follows these steps:

1. Convert the mass of the given reactant to moles: Use the reactant's molar mass.
2. Use the stoichiometric ratio from the balanced equation to find the moles of the product: This is done by dividing the moles of the reactant by its coefficient and then multiplying by the product's coefficient.
3. Convert the moles of the product to its mass (theoretical yield): Use the product's molar mass.

Example: Formation of Water

Consider the balanced chemical equation for the formation of water:

2 H₂ (g) + O₂ (g) → 2 H₂O (l)

Let's say you start with 10 grams of Hydrogen gas (H₂). We want to find the theoretical yield of water (H₂O).

• Reactant: H₂
• Product: H₂O
• Mass of Reactant (H₂): 10 g
• Molar Mass of Reactant (H₂): Approximately 2.016 g/mol
• Stoichiometric Coefficient of Reactant (H₂): 2
• Molar Mass of Product (H₂O): Approximately 18.015 g/mol
• Stoichiometric Coefficient of Product (H₂O): 2

Using the calculator with these values:

1. Moles of H₂: 10 g / 2.016 g/mol = 4.9603 mol H₂
2. Moles of H₂O: (4.9603 mol H₂ / 2) * 2 = 4.9603 mol H₂O
3. Theoretical Yield of H₂O: 4.9603 mol H₂O * 18.015 g/mol = 89.36 g H₂O

Therefore, the theoretical yield of water from 10 grams of hydrogen gas is approximately 89.36 grams.

This calculator simplifies the process by allowing you to input the necessary values directly, providing a quick way to determine the theoretical yield for various chemical reactions.