Chemistry
10th Edition
ISBN: 9781305957404
Author: Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher: Cengage Learning
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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 (Kf of water: 1.86°C/m, C: 12 g/mol, H: 1 g/mol, O: 16
g/mol)
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