Chapter 13 - Gas mixtures. This chapter develop rules for determining nonreacting gas mixture properties from knowledge of mixture composition and the properties of the individual components; define the quantities used to describe the composition of a mixture, such as mass fraction, mole fraction, and volume fraction; apply the rules for determining mixture properties to idealgas mixtures and real-gas mixtures. | Chapter 13 Gas Mixtures Study Guide in PowerPoint to accompany Thermodynamics: An Engineering Approach, 7th edition by Yunus A. Çengel and Michael A. Boles The discussions in this chapter are restricted to nonreactive ideal-gas mixtures. Those interested in real-gas mixtures are encouraged to study carefully the material presented in Chapter 12. Many thermodynamic applications involve mixtures of ideal gases. That is, each of the gases in the mixture individually behaves as an ideal gas. In this section, we assume that the gases in the mixture do not react with one another to any significant degree. We restrict ourselves to a study of only ideal-gas mixtures. An ideal gas is one in which the equation of state is given by Air is an example of an ideal gas mixture and has the following approximate composition. Component % by Volume N2 O2 Argon CO2 + trace elements For more information and animations illustrating this topic visit the . | Chapter 13 Gas Mixtures Study Guide in PowerPoint to accompany Thermodynamics: An Engineering Approach, 7th edition by Yunus A. Çengel and Michael A. Boles The discussions in this chapter are restricted to nonreactive ideal-gas mixtures. Those interested in real-gas mixtures are encouraged to study carefully the material presented in Chapter 12. Many thermodynamic applications involve mixtures of ideal gases. That is, each of the gases in the mixture individually behaves as an ideal gas. In this section, we assume that the gases in the mixture do not react with one another to any significant degree. We restrict ourselves to a study of only ideal-gas mixtures. An ideal gas is one in which the equation of state is given by Air is an example of an ideal gas mixture and has the following approximate composition. Component % by Volume N2 O2 Argon CO2 + trace elements For more information and animations illustrating this topic visit the Animation Library developed by Professor S. Bhattacharjee, San Diego State University, at this link. Definitions Consider a container having a volume V that is filled with a mixture of k different gases at a pressure P and a temperature T. A mixture of two or more gases of fixed chemical composition is called a nonreacting gas mixture. Consider k gases in a rigid container as shown here. k gases T = Tm V = Vm P = Pm m = mm The total mass of the mixture mm and the total moles of mixture Nm are defined as The properties of the mixture may be based on the mass of each component, called gravimetric analysis, or on the moles of each component, called molar analysis. Note that The composition of a gas mixture is described by specifying either the mass fraction mfi or the mole fraction yi of each component i. The mass and mole number for a given component are related through the molar mass (or molecular weight). To find the average molar mass
