102 Experiment 12 Determination of Molar Mass by the Freezing Point Depression Method 2. The equation AT; = Kçm is only strictly applicable to very. solutions. 3. The f.p. lowering (AT;) only depends on the molality and is independent of the nature of the solute. This is known as a property. 4. A solid is melted then allowed to cool and the temperature of the liquid is recorded every 2 minutes. According to the plot below, the most probable f.p. of the solid is . °C. 75.5 75.0 74.5 74.0 73.5 73.0 72.5 72.0 71.5 71.0 70.5 4 6. 8. 10 12 14 16 18 22 24 26 Time (min) Temperature (°C) 20 (Figure created by David Samo.) р. 102

102 Experiment 12 Determination of Molar Mass by the Freezing Point Depression Method 2. The equation AT; = Kçm is only strictly applicable to very. solutions. 3. The f.p. lowering (AT;) only depends on the molality and is independent of the nature of the solute. This is known as a property. 4. A solid is melted then allowed to cool and the temperature of the liquid is recorded every 2 minutes. According to the plot below, the most probable f.p. of the solid is . °C. 75.5 75.0 74.5 74.0 73.5 73.0 72.5 72.0 71.5 71.0 70.5 4 6. 8. 10 12 14 16 18 22 24 26 Time (min) Temperature (°C) 20 (Figure created by David Samo.) р. 102

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter11: Properties Of Solutions

Section: Chapter Questions

Problem 6RQ: In terms of Raoults law, distinguish between an ideal liquid-liquid solution and a nonideal...

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In terms of Raoults law, distinguish between an ideal liquid-liquid solution and a nonideal liquid-liquid solution. lf a solution is ideal, what is true about Hsoln, T for the solution formation, and the interactive forces within the pure solute and pure solvent as compared to the interactive forces within the solution? Give an example of an ideal solution. Answer the previous two questions for solutions that exhibit either negative or positive deviations from Raoults law.
A solution is made by dissolving 34.0 g of NaCl in 100 g of H2O at 0C. Based on the data in Table 8-1, should this solution be characterized as a. saturated or unsaturated b. dilute or concentrated
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A student determines the molar mass of acetone, , She found that the equilibrium temperature of a mixture of ice and water was 1.0C on her thermometer. When she added 11.1g of her sample to the mixture, the temperature, after through stirring, fell to -3.0C. She then poured off the solution through a screen into a beaker. The mass of the solution was 90.4g. a. what was the freezing point depression? b. what was the molarity of the acetone? c. how much aceton was in the decanted solution? d. how much water was in the decanted solution? e. how much acetone would there bein a solution containing 1kg of water and acetone at the same concentration as she has in herexperiment? f. what did she find to be the molar mass of aceton, assumingshe made the calculation properly?
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