2. A student was required to make a solution of camphor and naphthalene that had a freezing point of 166 C. How many grams of naphthalene (CjoHs) need to be added to 10.0 g of camphor to make this solution? The freezing point of pure camphor is 178.4°C and the freezing point depression constant for camphor, Kf, is 37.7°C/m. 3. The freezing point of biphenyl (molar mass 154 g/mole) is 71.0°C. When 1.240 g of benzophenone (molar mass 182 g/mole) is added to 9.52 g of biphenyl the solution is found to freeze at 14.3°C. Calculate the freezing point depression constant, Ks, for biphenyl. 4. You are given a vial with an unknown compound. You are told that it is a sodium halide compound. You need to determine the identity of the halide. When 1.57 g of NaX is added to 39.2 g of distilled water, the resulting solution was cooled and the freezing point was determined to be -1.45°C. What is the identity of X? (Assume the freezing point of the distilled water is 0.00°C.) 140

2. A student was required to make a solution of camphor and naphthalene that had a freezing point of 166 C. How many grams of naphthalene (CjoHs) need to be added to 10.0 g of camphor to make this solution? The freezing point of pure camphor is 178.4°C and the freezing point depression constant for camphor, Kf, is 37.7°C/m. 3. The freezing point of biphenyl (molar mass 154 g/mole) is 71.0°C. When 1.240 g of benzophenone (molar mass 182 g/mole) is added to 9.52 g of biphenyl the solution is found to freeze at 14.3°C. Calculate the freezing point depression constant, Ks, for biphenyl. 4. You are given a vial with an unknown compound. You are told that it is a sodium halide compound. You need to determine the identity of the halide. When 1.57 g of NaX is added to 39.2 g of distilled water, the resulting solution was cooled and the freezing point was determined to be -1.45°C. What is the identity of X? (Assume the freezing point of the distilled water is 0.00°C.) 140

Chemistry & Chemical Reactivity

9th Edition

ISBN:9781133949640

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter13: Solutions And Their Behavior

Section: Chapter Questions

Problem 104SCQ: Sodium chloride (NaCl) is commonly used to melt ice on roads during the winter. Calcium chloride...

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