Thermodynamics II course taught at air university Islamabad by Sijal Ahmed. In this lecture we have discussed about the gas-gas mixtures in very much details including how to find out the different thermodynamics properties for mixtures.

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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6. 6

7. 7

8. 8

9. 9

10. 10

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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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21. 21

22. 22

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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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