Raoult's law

Raoult's law is a law of thermodynamics established by French chemist François-Marie Raoult in 1887. It states that the partial vapor pressure of each component of an ideal mixture of liquids is equal to the vapor pressure of the pure component multiplied by its mole fraction in the mixture.

Mathematically, Raoult's law for a single component in an ideal solution is stated as

where ${\displaystyle p_{i}}$ is the partial vapor pressure of the component ${\displaystyle i}$ in the gaseous mixture (above the solution), ${\displaystyle p_{i}^{\star }}$ is the vapor pressure of the pure component ${\displaystyle i}$, and ${\displaystyle x_{i}}$ is the mole fraction of the component ${\displaystyle i}$ in the mixture (in the solution).

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