The document covers thermodynamics concepts related to gas mixtures, including mass and mole fractions, and key laws such as Dalton's Law of Partial Pressures and Amagat's Law of Additive Volumes. It discusses the behavior of ideal gas mixtures and the relationships between pressure, volume, and mole fraction, as well as properties of gas mixtures. Additionally, the document explains the evaluation of entropy in relation to gas mixtures at constant composition.

1. THERMODYNAMICS II
LECTURE 12
GAS MIXTURES
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2. Mass and Mole Fractions
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3. Mass and Mole Fractions
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4. Mass and Mole Fractions
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5. Mass and Mole Fractions
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12. P-V-T Behaviour of Gas Mixtures
• Ideal gas : molecules do not influenced by other molecules (low
densities  low pressure or high temperature).
• Dalton’s law of additive pressures, Amagat’s law of additive volumes.
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13. Dalton’s law of Partial Pressures
• The pressure of a gas mixture is equal to sum of the pressures each
gas would exert if it existed alone at the mixture temperature and
volume.
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14. Amagat’s law of additive volumes
• The volume of a gas mixture is equal to the sum of the volumes of
each gas would occupy, if it existed alone at the mixture pressure
and temperature.
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15. Relationship b/w Pressure, volume and mole fraction
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16. Relating p, V and T for Ideal Gas Mixtures
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17. Properties of Gas Mixture (Extensive)
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18. Properties of Gas Mixture (Intensive)
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19. Extensive and intensive properties
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25. Evaluating Entropy
• Entropy is function of pressure and temperature
• On molar basis:
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26. Mixture process at constant composition
• Composition is constant when it is going some process…
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27. • For constant properties :
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