# Mass fraction

Mass fraction refers to the fraction of a component in a solution when the amounts (component and solution) are expressed in mass (weight). In other words, mass fraction is the ratio of the mass (or weight) of a component to the total mass (or weight) of the solution.

_{i}) can be calculated by

_{i}= Mass of i

^{th}component of the solution

m_{tot} = Mass of the solution

Suppose a solution is prepared by dissolving two solutes A and B in a solvent C.

_{A})

_{B})

_{C})

_{A}= Mass of component A

_{B}= Mass of component B

m_{C} = Mass of component C

_{tot}) will be equal to

m_{tot} = m_{A} + m_{B} + m_{C}

_{A})

_{B})

_{C})

Since value of mass fraction is obtained by dividing mass of a component by total mass of the solution, it dimensionless. However, sometimes it is written as gram/gram or Kg/Kg.

**The sum of all mass fraction is equal to 1.**

ω_{A} + ω_{B} + ω_{C} = 1

**Independent of temperature**

In contrast to density, mass fraction is independent of temperature i.e., if temperature changes, the value of mass fraction does not change.