Most students reported molecular masses larger than the actual value. What is a possible reason for this? Your answer must be specific, simply saying "students made a mistake" is not sufficient. Molecular Weight Determination by Freezing Point DepressionObject:Determine the molecular mass of an unknown sample.Procedure:Add about 6 g of the solvent t-butanol to a test tube.Note – (Ks= 9.1°C/m)1.2.Place the test tube containing the t-butanol in a cold-water bath.3.Stir the liquid with a thermometer to determine the temperature in which t-butanol freezes.Do this twice using the same sample.4.Remove the test tube from the cold water bath and add about 0.4 g of the unknown sampleto the liquid t-butanol. Make sure the unknown sample dissolves completely.5.Repeat steps 2 and 3 with the test tube containing t-butanol and the unknown sample.Data:Mass of solvent (t-butanol)Freezing temperature of solvent°C°CMass of the unknown samplegFreezing temperature of the solution°C°CResults:Change in freezing temperature (AT;)°C°CMolality (m) of unknown solutionmmMolecular mass of unknown sample_g/mole_g/mole

The change in the properties associated with a given volume of solvent at a temperature value due to…

Answered: Most students reported molecular masses…

Most students reported molecular masses larger than the actual value. What is a possible reason for this? Your answer must be specific, simply saying "students made a mistake" is not sufficient.

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter10: Properties Of Solutions

Section: Chapter Questions

Problem 7RQ

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Question

Most students reported molecular masses larger than the actual value. What is a possible reason for this? Your answer must be specific, simply saying "students made a mistake" is not sufficient.

Molecular Weight Determination by Freezing Point Depression
Object:
Determine the molecular mass of an unknown sample.
Procedure:
Add about 6 g of the solvent t-butanol to a test tube.
Note – (Ks= 9.1°C/m)
1.
2.
Place the test tube containing the t-butanol in a cold-water bath.
3.
Stir the liquid with a thermometer to determine the temperature in which t-butanol freezes.
Do this twice using the same sample.
4.
Remove the test tube from the cold water bath and add about 0.4 g of the unknown sample
to the liquid t-butanol. Make sure the unknown sample dissolves completely.
5.
Repeat steps 2 and 3 with the test tube containing t-butanol and the unknown sample.
Data:
Mass of solvent (t-butanol)
Freezing temperature of solvent
°C
°C
Mass of the unknown sample
g
Freezing temperature of the solution
°C
°C
Results:
Change in freezing temperature (AT;)
°C
°C
Molality (m) of unknown solution
m
m
Molecular mass of unknown sample
_g/mole
_g/mole

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