Find the saturation values of mixing ratio for air of temperature 0 C and pressure 50 kPa
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Mixing ratio has different different definitions in different disciplines.
In Chemical Engineering, it refers to the mass ratio of water in air - ie the humidity generally expressed as grams of water per kilogram of air..
From the table in the link, the volumetric humidity of air at 0 degrees C is 4.8 grams per cubic meter.
The density of air at 0 degrees and normal pressure is 1.29 kilograms per cubic meter.
Therefore the mass ratio of saturated air at 0 degrees is 4.8/1.29 = 3.72 grams/kilogram (or 0.00372 as an absolute ratio)
In ideal gasses this ratio would be independent of pressure.
However water vapor is not quite an ideal gas and for highly accurate work, a correction factor must be applied.
In Chemical Engineering, it refers to the mass ratio of water in air - ie the humidity generally expressed as grams of water per kilogram of air..
From the table in the link, the volumetric humidity of air at 0 degrees C is 4.8 grams per cubic meter.
The density of air at 0 degrees and normal pressure is 1.29 kilograms per cubic meter.
Therefore the mass ratio of saturated air at 0 degrees is 4.8/1.29 = 3.72 grams/kilogram (or 0.00372 as an absolute ratio)
In ideal gasses this ratio would be independent of pressure.
However water vapor is not quite an ideal gas and for highly accurate work, a correction factor must be applied.