A chemist is given a nonelectrolyte white powder for analysis. 38.7 g of this substance is dissolved in 100.0 g of water. It is determined that the resulting solution freezes at -4.0°C. Additionally, the elemental composition of the substance is identified and found to be 40.0% C, 6.7% H and 53.3 % O by mass. Find the molecular formula of this unknown white powder using these experimental evidences (K of water: 1.86°C/m, C: 12 g/mol, H: 1 g/mol, O: 16 g/mol).

A chemist is given a nonelectrolyte white powder for analysis. 38.7 g of this substance is dissolved in 100.0 g of water. It is determined that the resulting solution freezes at -4.0°C. Additionally, the elemental composition of the substance is identified and found to be 40.0% C, 6.7% H and 53.3 % O by mass. Find the molecular formula of this unknown white powder using these experimental evidences (K of water: 1.86°C/m, C: 12 g/mol, H: 1 g/mol, O: 16 g/mol).

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 85QAP

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