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Re: K analyses

Jeff Dietsch asked:

> I remember people mentioning that Lamotte has
> one, but is the reason that no one else produces one due to
> supply/demand/cost?

The analysis is inherently difficult, hence expensive.

I know of two problems with analysing potassium.  First is simply that it
doesn't react with much of anything.  Most of our "wet chemistry" kits
depend on the analyte (potassium, in this case) reacting with something.
Second is that when it does react, sodium (which is typically much more
common than potassium and chemically similar to potassium) also reacts, so
while it may be possible to measure sodium+potassium, you can't measure
potassium alone.

If you dig up old analyses from water quality data bases you will find
many that list a single value for sodium+potassium.  In those cases there
was no analysis done for either sodium or potassium; their combined
concentration was determined by analysing all the other potentially
important ions and figuring out how much sodium and potassium had to be
present to nuetralize the charge of the analysed ions.  That was done to
cut costs.

Roger Miller