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Moist Air - Mole Fraction of Water Vapor

Mole fraction of water vapor is the ratio of water molecules to air and water molecules.

The mole fraction of water vapor is the ratio of the number of mole of water vapor in the moist air - to the total number of mole of dry air and water vapor.

The mole fraction of water vapor in moist air can be expressed as

xw = nw / (na + nw)                                            (1)

where

xw = mole fraction of water vapor

nw = mole of water

na = mole of air

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• Air Psychrometrics

Moist and humid air calculations. Psychrometric charts and Mollier diagrams. Air-condition systems temperatures, absolute and relative humidities and moisture content in air.

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Citation

• The Engineering ToolBox (2004). Moist Air - Mole Fraction of Water Vapor. [online] Available at: https://www.engineeringtoolbox.com/mole-fraction-humid-air-d_684.html [Accessed Day Month Year].

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7.8.15

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