I need to know the equation on calculating vapor pressur of asolution. I don't know what to plug in for what areas. The questionis: Safrole is used as a topical antiseptic. Calculate vaporpressure of a solution prepared by dissolving 0.75 mol of safrolein 950 g of ethanol (MM = 46.07 g/mol). Poethanol = 50.0torr at 25oC. I need to know the equation on calculating vapor pressur of asolution. I don't know what to plug in for what areas. The questionis: Safrole is used as a topical antiseptic. Calculate vaporpressure of a solution prepared by dissolving 0.75 mol of safrolein 950 g of ethanol (MM = 46.07 g/mol). Poethanol = 50.0torr at 25oC.
Explanation / Answer
Mass of ethanol = 950 g Molar mass = 46.07 g/mol Moles of ethanol = Mass / molar mass =950 g / 46.07 g/mol = 20.62 moles So total moles = 20.62 + 0.75 = 21.37 Mole fraction of solvent, ethanol = Moles of ethanol / totalmoles =20.62 / 21.37 = 0.964 Vapor pressure of solution = vapor pressure of solvent * molefraction of solvent =50 torr * 0.964 = 48.2 torr