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te m B. Determination of Molar Mass by Freezing Point Depression (25 points) 1. A pure solvent freezes at 12.0 °C and a pure solute freezes at 328.0 "C. A solution of 0.980 g of the and the molar mass of the solute is 178.2 g/mol. Calculate the freezing point depression constant solute and 13.870 g of the solvent freezes at 5.1 "C. The molar mass of the solvent is 154.2 g/mol for the solvent. (5 points) 2. Calcium chloride, CaCl, is commonly used as road salt. If one mole of CaCl, is dissolved in 1 kg of water, would the freezing point of the solution be greater than, less than, or the same as a Elution prepared by dissolving one mole of table sugar (sucrose, CH-01) in 1 kg of water? Explain your answer (5 points) 3. A student followed our lab procedure for this experiment. He started the experiment by measuring the mass and freezing point of the pure solvent with little error. Instead of quickly fininshing the experiment, he went to lunch. After returning from lunch, he noted that the solvent had absorbed some impurities from the atmosphere. He went ahead and performed the experiment anyway. Determine whether the measured freezing point depression (47) in the experiment would increase. decrease, or not change as compared to the value measured in an experiment where the solvent had no impurities in it (assume negligible change in the mass of the solvent after absorbing impurities). Also determine whether the measured molality of the soution (m) and the molar mass of the solute would increase, decrease, or not change. (10 points)