Mole Ratio Calculator Formula

Understand the math behind the mole ratio calculator. Each variable explained with a worked example.

Formulas Used

Moles of Unknown

moles_unknown = moles_known * (coeff_unknown / coeff_known)

Variables

VariableDescriptionDefault
moles_knownMoles of Known Substance(mol)3
coeff_knownCoefficient of Known2
coeff_unknownCoefficient of Unknown3

How It Works

How to Use Mole Ratios

Formula

moles_unknown = moles_known × (coeff_unknown / coeff_known)

The mole ratio comes directly from the balanced equation coefficients.

Worked Example

3 mol of A with 2A -> 3B. How many moles of B?

moles_known = 3coeff_known = 2coeff_unknown = 3
  1. 01Mole ratio = 3/2
  2. 02Moles B = 3 × (3/2) = 4.5 mol

Frequently Asked Questions

What is a mole ratio?

The ratio of coefficients from a balanced equation, showing how many moles of one substance react with or produce another.

Where do coefficients come from?

From the balanced chemical equation. They are the numbers placed before each formula.

Can I use this for any pair of substances?

Yes, for any two substances in the same balanced equation, use their respective coefficients.

Learn More

Guide

How to Balance Chemical Equations

Step-by-step guide to balancing chemical equations. Learn the law of conservation of mass, inspection method, tips for complex equations, and common mistakes.

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