ClarityKitFind a tool
Chemistry

Mole Fraction Calculator

Calculate the mole fraction of a component in a two-component mixture.

Explicit units and model assumptionsLocal calculations with worked examples
Chemistry workspace
Chemistry workspace

Check the units, concentration basis and assumptions before interpreting the result.

See the method

Set up your calculation

Runs on your device

Your chemistry result

Your result

Let’s calculate.

Use the Calculate button to see your result.

Review the method below for assumptions and conventions.

How to use this tool

  1. Enter component a amount, component b amount.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

The method, explained

xA = nA ÷ (nA + nB). xB = 1 − xA. Mole percent = mole fraction × 100.

A WORKED EXAMPLE

Using component a amount = 2 mol, component b amount = 3 mol, the result is 0.4. Change these example inputs to match your task; use the method above to check each step.

Understanding your result

No. Convert each mass to moles using its own molar mass first. A mass fraction and a mole fraction are generally different.

What to keep in mind

For more than two components, combine all components other than A into the B input. Educational calculation only; use validated procedures for laboratory work.

Reference: OpenStax Chemistry 2e — chemical quantities and models

Common questions

Can I enter masses directly?

No. Convert each mass to moles using its own molar mass first. A mass fraction and a mole fraction are generally different.

Are my inputs uploaded?

No. This calculation runs in your browser without an account or an external API.

Methodology maintained by ClarityKit. How these tools are built and checked.