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Unit 7.5. Gas Mixtures: Partial Pressures and Mole fractions. VI) (7.5) Gas Mixtures: Partial Pressures and Mole fractions. iii). are the pressures of the gases if they were alone. and. a) Introduction:. i.) The ideal gas law applies to pure gases and gas mixtures.
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Unit 7.5 Gas Mixtures: Partial Pressures and Mole fractions
VI) (7.5) Gas Mixtures: Partial Pressures and Mole fractions iii) are the pressures of the gases if they were alone. and a) Introduction: i.) The ideal gas law applies to pure gases and gas mixtures ii) For a mixture of two gases (A and B), the total pressure is given by the expression: These are called partial pressures iv) So: Ptot = PA + PB v) This is referred to as Dalton’s Law of partial pressures: The total pressure of a gas mixture is the sum of the partial pressures of the components of the mixture.
VI) (7.5) Gas Mixtures: Partial Pressures and Mole fractions b) Wet Gases; Partial pressure of water: i) When any gas is collected by bubbling through water, it picks up water vapor. ii) Dalton’s law of partial pressures can be applied to the resulting gas mixture: 1) Ptot = Pwater + Pother 2) Pwater is a fixed value at any given temperature. (appendix 1)