One quiet night, I was musing over moisture analysis and how easy it is to do using loss-on drying. Little did I know what was in store.
Of course, everybody knows that all you do is 1. weigh a sample, 2. dry it out and then 3. weigh it again. However,
Do I talk about it all at once or break it into individual mysteries? I found the former approach overwhelming, but with respect to the latter --- Where to start?
After brooding for a while, I concluded that evaporation was important to the loss-on
It seems that evaporation is all about water molecules bumping into each other. If they are highly agitated by an energy source, they fly away from their neighbors and transform a closely packed liquid into a loosely packed
When things settle into equilibrium, the gas
The energy, usually heat, gets the highly agitated molecules to fly out of the
All of these influence loss-on drying tests. I thought it was “just turn on the heat and wait;” -- No considerations of bouncing molecules, summer or winter, clear or stormy weather to confuse and change evaporation.
Now we know some of the reasons that loss-on drying tests sometimes take longer or shorter than normal periods.
Maybe, someday I'll get the courage to take on vapor pressure, water content, drying and even water activity. Look for it.
Thanks for reading this rant, hope it was amusing and maybe helpful.
As always, a mystified,
Art
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P.P.S. See where Loss On Drying works best