The melting point of solvents is depressed in the presence of solutes. The depression brought about by dissolving 1 mol of solute in 1,000 g of solvent is known as the 'cryoscopic constant.' For example, in the Rast method for determining molecular weight, camphor with a melting point of 179°C is used as the solvent. When 1 mol of a compound is dissolved in 1,000 g of camphor, it brings the melting point of the solution down to 139°C (cryoscopic constant = 40). The following data are: • Weight of camphor: 1.80 g Weight of the unknown: 0.054 g Melting point of the solution: 165°C How much is the molecular weight of the unknown? Show your calculation below.

The melting point of solvents is depressed in the presence of solutes. The depression brought about by dissolving 1 mol of solute in 1,000 g of solvent is known as the 'cryoscopic constant.' For example, in the Rast method for determining molecular weight, camphor with a melting point of 179°C is used as the solvent. When 1 mol of a compound is dissolved in 1,000 g of camphor, it brings the melting point of the solution down to 139°C (cryoscopic constant = 40). The following data are: • Weight of camphor: 1.80 g Weight of the unknown: 0.054 g Melting point of the solution: 165°C How much is the molecular weight of the unknown? Show your calculation below.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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