Determine the freezing point of a solution that contains 62.8 g of urea (CH₄N₂O)dissolved in 275 g of water (K_f= 1.86°C/m). A) -7.07°C B) -4.82°C C) -13.1°C D) -3.01°C E) -9.12°C

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Quizplus · Accepted Answer

The correct answer is A because the freezing point depression is calculated using the formula ΔTf = Kf * molality, where Kf is the freezing point depression constant for the solvent (water) and molality is the concentration of the solution in moles of solute per kilogram of solvent. The molality of the solution is calculated by dividing the moles of urea by the mass of water in kilograms. The moles of urea are calculated by dividing the mass of urea by its molar mass. The mass of water in kilograms is calculated by dividing the mass of water by 1000. The freezing point depression is then calculated by multiplying the molality by the freezing point depression constant for water. The freezing point of the solution is then calculated by subtracting the freezing point depression from the freezing point of pure water (0°C).

Determine the Freezing Point of a Solution That Contains 62