B) If the temperature at point (a) on the above graph is 0.1 °C, and the temperature atpoint (b) is -3.5 °C, what is the ATr of the solution?C) 1.25 grams of an unknown compound is dissolved into 85.0 grams of benzene, anorganic solvent with a freezing point depression constant, Kf = 5.12 °C/m. The freezingpoint of the pure benzene is 5.51°C and the freezing point of the solution is 4.50 °C.Find the molar mass (molecular weight) of the unknown compound. 2. Determination of Molar Mass by Freezing Point Depressionbe able to interpret a cooling curve, calculate molar mass and use i factors infreezing point depression calculationsTemperature vs. Cooling Time for Solvent and Solution7(0)(a)BATPPura SultTime of Cong1000SectingSolutionf)Freezing point ofpure solverezing pistetsolutionFigure 1. Freezing Point Graph for Pure Solvent and for SolutionA) If the two cooling curves shown above had not been labelled to indicate which one isthe pure solvent, and which one is the solution, would you be able to distinguishthem? If so, explain how you would know which one is which.1

Answered: Image /qna-images/answer/89e279ef-f711-45e4-88ae-656002ea8bf2.jpg

B) If the temperature at point (a) on the above graph is 0.1 °C, and the temperature at point (b) is -3.5 °C, what is the ATr of the solution? C) 1.25 grams of an unknown compound is dissolved into 85.0 grams of benzene, an organic solvent with a freezing point depression constant, Kr= 5.12 °C/m. The freezing point of the pure benzene is 5.51°C and the freezing point of the solution is 4.50 °C. Find the molar mass (molecular weight) of the unknown compound.

B) If the temperature at point (a) on the above graph is 0.1 °C, and the temperature at point (b) is -3.5 °C, what is the ATr of the solution? C) 1.25 grams of an unknown compound is dissolved into 85.0 grams of benzene, an organic solvent with a freezing point depression constant, Kr= 5.12 °C/m. The freezing point of the pure benzene is 5.51°C and the freezing point of the solution is 4.50 °C. Find the molar mass (molecular weight) of the unknown compound.

Chemistry: Principles and Reactions

8th Edition

ISBN:9781305079373

Author:William L. Masterton, Cecile N. Hurley

Publisher:William L. Masterton, Cecile N. Hurley

Chapter10: Solutions

Section: Chapter Questions

Problem 73QAP: Consider three test tubes. Tube A has pure water. Tube B has an aqueous 1.0 m solution of ethanol,...

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Concept explainers

Solutions

Solutions can be considered as homogeneous mixtures which contain two or more than two chemical substances. The chemical substance which is the greater part is defined as solvent. And the chemical substance that is dissolved in a solvent is referred to as solute. Solution chemistry plays an important role in chemistry since it supports many commercial applications of solutions.

Question

B) If the temperature at point (a) on the above graph is 0.1 °C, and the temperature at
point (b) is -3.5 °C, what is the ATr of the solution?
C) 1.25 grams of an unknown compound is dissolved into 85.0 grams of benzene, an
organic solvent with a freezing point depression constant, Kf = 5.12 °C/m. The freezing
point of the pure benzene is 5.51°C and the freezing point of the solution is 4.50 °C.
Find the molar mass (molecular weight) of the unknown compound.

2. Determination of Molar Mass by Freezing Point Depression
be able to interpret a cooling curve, calculate molar mass and use i factors in
freezing point depression calculations
Temperature vs. Cooling Time for Solvent and Solution
7(0)
(a)
B
ATP
Pura Sult
Time of Cong
1000
Secting
Solution
f)Freezing point of
pure solvere
zing pistet
solution
Figure 1. Freezing Point Graph for Pure Solvent and for Solution
A) If the two cooling curves shown above had not been labelled to indicate which one is
the pure solvent, and which one is the solution, would you be able to distinguish
them? If so, explain how you would know which one is which.
1

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