where P A is the partial pressure exerted by component A in the solution, \(P^\circ_\ce{A}\) is the vapor pressure of pure A, and X A is the mole fraction of A in the solution. (Mole fraction is a con...where P A is the partial pressure exerted by component A in the solution, \(P^\circ_\ce{A}\) is the vapor pressure of pure A, and X A is the mole fraction of A in the solution. (Mole fraction is a concentration unit introduced in the chapter on gases.)
