I started by weighing-in with a shot at interpreting evaporation, while hinting that I'd take on the other principles that effect loss-on-drying moisture tests at some point in the future.
I've decided to have a go at vapor pressure. Why vapor pressure now --- because it's next on the list.
I guess as good a place to start as any, is with a definition:
To refresh the image , from the past musing on Moisture Mysteries, of evaporation,
This vapor pressure is a unique characteristic of a pure liquid. The molecular bonding of the pure liquid defines its unique vapor pressure.
Weak bonding high vapor pressure
Strong bonding low vapor pressure
To see how it works you have to look at the dynamics. Dynamics have always complicated my life.
For any pure liquid, dynamics fortunately are only related to
Fortunately for our understanding, the surface area of a liquid has zero effect on Vapor Pressure. I'm not 100% sure why I even mention this except that if this was not a constant, it would confuse the energy issues related to getting evaporation, which is why we started this whole rant.
Because we are rambling about moisture, the liquid we refer to will be water.
To generate evaporation and get the water out , which we need to do when we conduct Loss On
That's how Vapor Pressure relates to a loss-on-drying moisture test.
I'm not sure but, in future ramblings, I might take on water content complexities, water activity witchcraft and just plain drying. Should I?
See What I Tried.
I hope this expose/rant was somewhat interesting and useful. I welcome your comments. Thanks for reading it.
As usual a perplexed,
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