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Heptane, C7H16, and octane, C8H18, form ideal solution. The solution boils at 85.00 ºC and 0.522 atm. (At 85.00 ºC, the vapor pressure of pure heptane is 0.570 atm and the vapor pressure of pure octane is 0.234 atm.)
What is the vapor pressure above the solution if the mole fraction of octane is 0.234?