4) In determining the identity of an unknown compound used in making resins, 0.134g of the compound was dissolved in 20.0g dimethyl sulfoxide (DMSO). The solution froze at 18.315 °C. a) What is the molality of the unknown compound? For DMSO, Tr= 18.52 °C; Kr = 3.85°C.kg/mol. b) How many moles of the unknown compound is present in the solution? c) What is the molar mass of the unknown compound? d) If the empirical formula of the unknown compound is CH2N2, what is its molecular formula?

4) In determining the identity of an unknown compound used in making resins, 0.134g of the compound was dissolved in 20.0g dimethyl sulfoxide (DMSO). The solution froze at 18.315 °C. a) What is the molality of the unknown compound? For DMSO, Tr= 18.52 °C; Kr = 3.85°C.kg/mol. b) How many moles of the unknown compound is present in the solution? c) What is the molar mass of the unknown compound? d) If the empirical formula of the unknown compound is CH2N2, what is its molecular formula?

Chemistry: Principles and Practice

3rd Edition

ISBN:9780534420123

Author:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Publisher:Daniel L. Reger, Scott R. Goode, David W. Ball, Edward Mercer

Chapter12: Solutions

Section: Chapter Questions

Problem 12.51QE

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