When people are looking for a way to measure small amounts of moisture, we often recommend the Karl Fischer method.
I thought it might be interesting to answer the second
First, I climbed into a jar that has four openings at the top.
Through one of the
Next, through another opening, they push a second glass tube that has wires sticking
Sitting at the bottom of this jar is a little rod, which they call the Stirrer.
Comfortably sitting on the stirrer rod at
Then, they tell me to be ready to swim as they fill the main part of the jar about halfway with another liquid they refer to as the Reagent. As I'm treading water in this reagent, they seal off all the openings so they are air-tight.
They yell down that they are going to start clearing out all of
As I'm bouncing around the jar -- or as the operators call it the Titration Cell -- they tell me to be ready for a little shock. They turn on the machine and the detector says, "Hey! There is water in here. Push some electric current into the cell." Zap Zap Zap.......
The maelstrom starts to turn yellow. What is this? It is a whole bunch of Iodine; the very same substance you used to put on a cut finger.
They tell me that the shock I felt caused the Reagent to produce the Iodine. Apparently, the Iodine reacts with the water and gets rid of it.
By that time, the detector says, "Water's All Gone" and they turn off the stirrer. I'm almost drowned.
An operator yells down, "Here comes a real test!" The dammed stirrer starts and I'm in the blender again.
I'm racked with shocks for a minute or two and the yellow returns. The Iodine does its job and the detector says, "No More Water."
The shocks stop. The test is over. The operators shut down the stirrer and pull me out --- totally waterlogged. Or should I say reagent-logged?
The machine measured the amount of shock it took to generate enough Iodine to get rid of the water. All of this was done just to measure a few micrograms of water.
I hope you found this amusing and maybe a little informative. If you found this useful, share it with associates who deal with moisture measurement.
By the way, I am never going inside a Karl Fischer Titration Cell again.
A very soggy Art
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