A solution contains naphthalene (C10H8) dissolved in hexane (C6H14) at a concentration of 12.35% naphthalene by mass. Calculate the vapor pressure of hexane above the solution at 25 °C. The vapor pressure of pure hexane at 25 °C is 151 torr.

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Determine the mass of naphthalene and hexane in the solution. Assume a total mass of 100 g for simplicity, which means 12.35 g of naphthalene and 87.65 g of hexane.

Calculate the number of moles of naphthalene (C_{10}H_{8}) using its molar mass (128.17 g/mol).

Calculate the number of moles of hexane (C_{6}H_{14}) using its molar mass (86.18 g/mol).

Find the mole fraction of hexane in the solution using the formula: \( \text{Mole fraction of hexane} = \frac{\text{moles of hexane}}{\text{moles of hexane} + \text{moles of naphthalene}} \).

Apply Raoult's Law to find the vapor pressure of hexane above the solution: \( P_{\text{solution}} = \chi_{\text{hexane}} \times P^0_{\text{hexane}} \), where \( P^0_{\text{hexane}} \) is the vapor pressure of pure hexane (151 torr).

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