
Concept explainers
An organic compound contains carbon (71.17%), hydrogen (5.12%) with the remainder nitrogen. Dissolving 0.177 g of the compound in 10.0 g of benzene gives a solution with a vapor pressure of 94.16 mm Hg at 25 °C. (The vapor pressure of pure benzene at this temperature is 95.26 mm Hg.) What is the molecular formula for the compound?

Interpretation Molecular formula of the compound has to be determined.
Concept introduction:
Raoult’s law: In a solution, vapor pressure of solvent is proportional to its mole fraction.
where,
Mole fraction: Amount of that component divided by the total amount of all of the components of the mixture
The number of moles of any substance can be determined using the equation
Answer to Problem 91IL
Molecular formula of the compound is
Explanation of Solution
Molecular formula of the compound is calculated.
Given,
Molar mass of carbon is
Molar mass of hydrogen is
Molar mass of nitrogen is
Vapour pressure of benzene at
Vapour pressure of pure benzene is
Mass of the compound is
Mass of benzene is
Molar mass of benzene is
The number of moles of any substance can be determined using the equation
Number of moles of benzene is
Vapour pressure of benzene is calculated by the given equation
Mole fraction of benzene is,
Hence,
Number of moles of the compound is
Hence,
The molar mass of compound is,
Number of moles of carbon is
Number of moles of hydrogen is
Empirical formula of the compound was determined.
Therefore,
The empirical formula of the compound is
Molecular mass of
The molar mass of a molecule is a simple multiple of the molar mass of its empirical formula. Hence,
Therefore,
Molecular formula of the compound is
Molecular formula of the compound is
Want to see more full solutions like this?
Chapter 13 Solutions
Chemistry & Chemical Reactivity
Additional Science Textbook Solutions
Biology: Life on Earth (11th Edition)
Campbell Biology (11th Edition)
Cosmic Perspective Fundamentals
Biology: Life on Earth with Physiology (11th Edition)
Fundamentals Of Thermodynamics
- I need the most help figuring out how to find [I^-] mol/ L, [S2O8^2-] mol/L. 1st and 2nd Blank columns.arrow_forwardCan someone help me whats the issue?arrow_forwarda. The change in the Gibbs energy of a certain constant pressure process is found to fit the expression: AG-85.1 J mol −1 +36.5 J mol ¹K-1 × T A. Calculate the value of AS for the process. B. Next, use the Gibbs-Helmholtz equation: (a(AG/T)) ΔΗ - T2 to calculate the value of AH for the process.arrow_forward
- Consider the structure of 1-bromo-2-fluoroethane. Part 1 of 2 Draw the Newman projection for the anti conformation of 1-bromo-2-fluoroethane, viewed down the C1-C2 bond. ✡ ぬ Part 2 of 2 H H F Br H H ☑ Draw the Newman projection for the gauche conformation of 1-bromo-2-fluoroethane, viewed down the C1-C2 bond. H F Br H Harrow_forwardPlease help me answer this question. I don't understand how or where the different reagents will attach and it's mostly due to the wedge bond because I haven't seen a problem like this before. Please provide a detailed explanation and a drawing showing how it can happen and what the final product will look like.arrow_forwardWhich of the following compounds is the most acidic in the gas phase? Group of answer choices H2O SiH4 HBr H2Sarrow_forward
- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781337399074Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage LearningChemistry & Chemical ReactivityChemistryISBN:9781133949640Author:John C. Kotz, Paul M. Treichel, John Townsend, David TreichelPublisher:Cengage Learning
- World of Chemistry, 3rd editionChemistryISBN:9781133109655Author:Steven S. Zumdahl, Susan L. Zumdahl, Donald J. DeCostePublisher:Brooks / Cole / Cengage LearningChemistry: Principles and ReactionsChemistryISBN:9781305079373Author:William L. Masterton, Cecile N. HurleyPublisher:Cengage Learning




