Help with Raoult's law

Raoult's law is a law of thermodynamics established by French physicist François-Marie Raoult in 1882. [1] 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. The total vapor pressure of the ideal solution is then directly dependent on the vapor pressure of each chemical component and the mole fraction of the component present in the solution.[2]

Once the components in the solution have reached equilibrium, the total vapor pressure p of the solution is: \scriptstyle p = p^{\star}_{\rm A} x_{\rm A} + p^{\star}_{\rm B} x_{\rm B} + \cdots and the individual vapor pressure for each component is \scriptstyle p_i = p^{\star}_i x_i where pi is the partial vapor pressure of the component i in the gaseous mixture (above the solution), p*i is the vapor pressure of the pure component i, and xi is the mole fraction of the component i in the mixture (in the solution).

If a pure solute which has zero vapor pressure (it will not evaporate) is dissolved in a solvent, the vapor pressure of the final solution will be lower than that of the pure solvent.

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