This chemistry calculator computes mole fractions and mole percentages for a binary mixture from solute and solvent amounts.
Chemistry
Mole Fraction Calculator
Calculate component mole fractions and mole percentages for a binary solution.
Calculator
About this calculator
Formula notes
total = solute + solvent; solute fraction = solute / total; solvent fraction = solvent / total; percent = fraction x 100.
Worked examples
- Example: 1 mol solute with 4 mol solvent gives a solution total of 5 mol; the solute fraction is 0.2 (20%) while the solvent fraction is 0.8 (80%).
- 100 mol solute plus 900 mol solvent gives solution total 1,000 mol, solute fraction 0.1, and solvent fraction 0.9.
How to use it
- Enter solute moles and solvent moles.
- Keep both values in the same moll basis.
- Read solution moles, fractions, and percentages.
Frequently asked questions
What if I know mass or volume?
Convert concentrations or volumes into moles first, using molar masses or molarity before entering the tool.
Does the fraction sum to one?
Yes for a binary solution: solute fraction plus solvent fraction equals exactly 1.
Limits and interpretation
- Mole fractions describe composition in mole amount, not mass or volume; converting between them requires molar mass or molarity assumptions.
- The formula assumes a two-component mixture; activity coefficients, volatility, and solution non-ideality are outside the tool.