# Molar fraction definition

Molar fraction is defined as ratio of number of moles of substance to total number of moles of all substances. For example 10 molal water solution of ethanol contains 10 moles of ethanol for every 1000 g of water. 1000 g of water is 55.51 mole - and molar fraction of ethanol is

10/(55.51+10)=0.1527.

Molar fractions are temperature independent.

Molar fractions can be used for mixtures of any number of compounds. Maximum molar fraction is always 1 and sum of molar fractions of all substances is always 1 too.

To convert between molar fractions and other concentration types both molar masses of solvent and solute are needed.

Molar fractions are unitless.