What is mole fraction? Explain in brief.

(N/A) Definition: The ratio of the number of moles of a specific component to the total number of moles of all components in a solution is known as the mole fraction of that component.
The symbol used for mole fraction is $x$,and the subscript denotes the specific component.
Mole fraction of a component $= \frac{\text{Number of moles of the component}}{\text{Total number of moles of all the components}}$
For a binary mixture with $n_{A}$ moles of component $A$ and $n_{B}$ moles of component $B$,the mole fraction of $A$ is given by:
$x_{A} = \frac{n_{A}}{n_{A} + n_{B}}$
For a solution containing $i$ components,the mole fraction of component $i$ is:
$x_{i} = \frac{n_{i}}{\sum n_{i}}$
The sum of all mole fractions in a solution is always unity:
$x_{1} + x_{2} + \ldots + x_{i} = 1$
Mole fraction is useful in relating physical properties like vapour pressure to concentration and is essential for calculations involving gas mixtures.