"Morgans" wrote in message
...

"Peter Dohm" wrote

Really, the only way that I know to correctly "do the science" is to
purchase a small amount (perhaps a liter) of anhydrous ethanol from a
medical supply and perform a series of tests on a variety of
samples--including samples of known pure and dry avgas and mogas. For
the
moment, I am unwilling to undertake the project, and also I believe that
Clare and Bob are correct.

How sure are we that the gasohol in service station tanks contain no
water?

Is it possible that all tanks containing gasohol contain at least some
water
dissolved?

Is it a certainty that the alcohol added to gasoline contains no dissolved
water?

I don't know the answer to any of these questions. Does anyone know, for
CERTAIN, any of these questions?

My guess is that all service station tanks, (unless they have never had
straight gas, and that they are BRAND NEW) have had an opportunity to get
some water in their tanks. If that is the case, and you put gasohol in
them, the gasohol samples will contain some dissolved water, and the
seltzer
test will work.

If that is the case, doing a scientific test with clean gas and adding
water
free alcohol will prove nothing.
--
Jim in NC


According to annecdotes that I heard many years ago, service station gas
tanks have always contained some water--but since the gasolene is lighter,
the water settled to the bottom, so they were able to draw straight gasolene
from a floating pickup. According to those annecdotes, there could have
been as much as a couple of feet on water below the gasolene before it was
drawn of as part of periodic maintenance, with the result that the apparatus
were designed to shut off with a considerable level of liquid remaining in
the tanks--in order to avoid pumping water.

At this time, I have no reliable means to verify the the original story, nor
whether service stations now have sealed tanks with evaporative controls and
driers similar to the vehicles they service--which I doubt.

However, one obvious possibility is as droll as it is annoying.

Peter