|MadSci Network: Engineering|
In short, no they are not the same. Relative humidity is the amount of moisture carried in the air, relative to the maximum amount that can be carried at that temperature and expressed as a percentage. For example, air at a temperature of 60F has a carrying capacity of approximately 0.011 pounds of water per pound of dry air. If this temperature is actually carrying 0.0055 pounds of water per pound of dry air then the humidity will be 50%. The carrying capacity is a strong function of temperature. The second part of your question is harder. It is a question about equilibrium distribution. Generally speaking, if you have two different phases, such as air and water, any chemical compound will distribute itself between the two phases. For example, if you have air and water in contact, some of the oxygen will exist in the air as a gas, and some of it will dissolve in the water. The amount which goes into each phase depends on the chemical nature of the phases and the compound of interest, in this case oxygen. The partition coefficient for the particular system will tell you this. For your case, the two phases are air and wood. The compound of interest is water and you want to know its equilibrium distribution between the two phases (partition coefficient). It might even be different for different kinds of wood. Good luck with your search!
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