Determine the vapor pressure of a solution at 25°C that contains 85.3 g of naphthalene (C₁₀H₈)in 540 g of benzene (C₆H₆).The vapor pressure of benzene at 25°C is 74.6 torr. A) 74.6 toff. B) 68.0 torr. C) 54.9 torr. D) 7.52 torr. E) 22.4 toff.

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The vapor pressure of the solution is calculated using Raoult's Law. First, calculate the mole fraction of benzene. Moles of naphthalene = 85.3 g / 128.17 g/mol = 0.666 mol. Moles of benzene = 540 g / 78.11 g/mol = 6.914 mol. Mole fraction of benzene = 6.914 / (6.914 + 0.666) = 0.912. Vapor pressure of solution = 0.912 * 74.6 torr = 68.0 torr.

Determine the Vapor Pressure of a Solution at 25°C That