# Reaction Stoichiometry Calculator

Determine the limiting reagent and compute theoretical yield, actual yield, and percent yield from a balanced reaction.

> Canonical page: https://elysiatools.com/en/tools/reaction-stoichiometry-calculator

- **Category:** Math & Numbers

- **Keywords:** stoichiometry, limiting reagent, theoretical yield, percent yield, chemistry

## Overview

The Reaction Stoichiometry Calculator helps you quickly identify the limiting reagent and calculate the theoretical, actual, and percent yield of a chemical reaction. By inputting balanced reactant coefficients, formulas, and masses alongside your target product, you can instantly determine reaction efficiency and material requirements without manual molar mass calculations.

## Inputs

- **Reactants (name, formula, mass)** (textarea): Each line: optional label, stoichiometric coefficient + chemical formula, and the available mass (g/kg/mg).
- **Target Product Formula** (text): Chemical formula of the product whose yield you want. Include its stoichiometric coefficient (e.g. 2 H2O).
- **Actual Yield (g)** (number): Optional — leave blank to compute theoretical yield only
- **Decimal Places** (number)

## When to use

- When preparing laboratory experiments and needing to identify which reactant will limit the product yield.
- When calculating the percent yield of a completed chemical reaction to evaluate synthesis efficiency.
- When solving stoichiometry homework problems or verifying manual molar mass and mole ratio calculations.

## How it works

- Enter each reactant on a new line, specifying its stoichiometric coefficient, chemical formula, and available mass (e.g., '2 H2, 1.0 g').
- Input the target product formula along with its stoichiometric coefficient (e.g., '2 H2O').
- Optionally provide the actual yield obtained in grams and set your preferred decimal precision.
- Click calculate to parse the chemical formulas, determine molar masses, identify the limiting reagent, and output the theoretical and percent yields.

## Use cases

- Determining the limiting reactant and theoretical yield for a water synthesis reaction using hydrogen and oxygen gases.
- Calculating the percent yield of an organic synthesis experiment by comparing the recovered product mass against the theoretical maximum.
- Verifying stoichiometry homework solutions for chemistry students and educators.

## Frequently asked questions

### How do I format the reactant inputs?

Enter one reactant per line, starting with its stoichiometric coefficient, followed by the chemical formula, a comma, and the mass (e.g., '1 O2, 8.0 g').

### Can I use mass units other than grams?

Yes, you can specify units like g, kg, or mg directly in the reactant mass field.

### What is a limiting reagent?

It is the reactant that is completely consumed first in a chemical reaction, limiting the amount of product that can be formed.

### How is the percent yield calculated?

It is calculated by dividing the actual yield by the theoretical yield and multiplying by 100.

### Do I need to balance the chemical equation first?

Yes, you must include the correct stoichiometric coefficients from a balanced equation for both reactants and the target product.

## Related tools

- [Absolute Value Calculator](https://elysiatools.com/en/tools/absolute-value-calculator): Calculate the absolute value of positive, negative, or decimal numbers and explain the sign relationship
- [Adjusted R-Squared Calculator](https://elysiatools.com/en/tools/adjusted-r-squared-calculator): Calculate adjusted R squared from R squared, sample size, and predictor count
- [Air Changes per Hour (ACH, n = Q/V)](https://elysiatools.com/en/tools/air-changes-per-hour): Compute the air change rate (ACH / n) of a room from the outdoor supply airflow Q and the room volume V: n = Q/V (1/h). Three modes: solve ACH (given Q and V), solve airflow (given n and V), or solve volume (given n and Q). Flow in m³/s/m³/h/CFM, volume in m³/ft³/L. Also reports the well-mixed single-zone purge time to reach a target residual fraction ε (default 1%): t = −ln(ε)/n hours.
- [Bearing Life L10 Calculator](https://elysiatools.com/en/tools/bearing-life-l10): Calculate the basic rating life of a rolling bearing: L10 = (C/P)^p, with p = 3 for ball bearings and p = 10/3 for roller bearings. When a speed is provided, converts to L10h in operating hours.
- [Bolt Torque Clamp Force Calculator](https://elysiatools.com/en/tools/bolt-torque-clamp-force): Convert between bolt tightening torque and axial clamp force. T = K·F·d, where K is the nut factor (~0.20 for dry steel). Solve torque from force, or force from torque.
- [Cable Ampacity Calculator (IEC 60364-5-52)](https://elysiatools.com/en/tools/cable-ampacity-calculator): Estimate copper cable current-carrying capacity per the simplified IEC 60364-5-52 reference method. Combines cross-section, insulation (PVC 70°C / XLPE 90°C), installation method, and ambient temperature to derive the corrected allowable ampacity (A).
- [Capacitor Reactive Power Calculator (Q_c = 2πfCU²)](https://elysiatools.com/en/tools/capacitor-reactive-power): Compute the reactive power produced by a known capacitor: Q_c = 2π·f·C·U². Supports single-phase, three-phase star (Y) and delta (Δ) connections. Returns Q_c in var/kvar, capacitive reactance Xc, and capacitor current Ic. Complementary to the power-factor-correction tool (which sizes a capacitor for a target cosφ).
- [Chain Sprocket Ratio Calculator](https://elysiatools.com/en/tools/chain-sprocket-ratio): Calculate the ratio, driven speed and chain linear speed of a chain drive. i = z₂/z₁ = n₁/n₂, chain speed v = z₁·p·n₁/60000. Enter the pitch to compute chain speed.

## Samples

- [Web Image Processing Python Samples](https://elysiatools.com/en/samples/web-image-processing-python): Web Python image processing examples using PIL/Pillow including reading, saving, resizing, and format conversion
- [Android Image Processing Java Samples](https://elysiatools.com/en/samples/android-image-processing-java): Android Java image processing examples including reading/saving images, scaling, and format conversion
- [Android Image Processing Kotlin Samples](https://elysiatools.com/en/samples/android-image-processing-kotlin): Android Kotlin image processing examples including reading/saving images, scaling, and format conversion
- [Web Image Processing Rust Samples](https://elysiatools.com/en/samples/web-image-processing-rust): Web Rust image processing examples including image read/save, scaling, and format conversion