Re: General Questions

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Dr. Duncan Cadd by way of Terry Fritz <twftesla-at-uswest-dot-net>" <dunckx-at-freeuk-dot-com>

Hi Jason, All!

Whoaup lad!  This chemistry is tricky stuff (and perilously near off
topic*) and there's few things so weird and wonderful as water, of
which ye and me are living proof!  (Well, OK, antimony pentafluoride
is pretty whacky but I wouldn't want a bath in it ;-)

>but by default water is an ionic compound and therefore a charge
carrier! in
>this way, you CANT have de-ionised water because water itself is
ionic!!!


Well, yes, water is an ionic compound, but in the absence of any ionic
impurities, the equilibrium lies well away from the fully dissociated
state, in fact there's scarcely any free H+ or HO- at all!  "To make
gold, you must take gold" as the old alchemists used to say, and if
you want dissociated ions, you must add dissociated ions.  In the
total absence of extraneous muck (technical term) only one in 10^14
water molecules is dissociated at room temperature.

>The H+ ions will move electrons around very efficiently, and even a
high
>resistivity will not really be enough to stop a large amount of
voltage!


If the water is clean enough, you can use it to cool high power valve
transmitters which have the water flowing through the anode at say
20kV - on a continuous basis.  Usually you help things by using narrow
bore insulating hose maybe a hundred feet long.  That way the total
resistive path via the water is more ohms.  This is old technology,
the stuff which existed before modern ion exchange resins were
invented; water-cooled valves date back to the 1920s and some are
displayed in the Science Museum, London (or were a few years ago) in
their radio exhibit.  What Jim et al have said is true.  *Really*
clean water is a very good insulator, but the ionic impurities (e.g.
sodium, sulphate, chloride etc ions) do have to be sub-ppm (and
probably sub-ppb) for the more impressive applications, like the 500kV
dc switching converter (does this thing have a web presence?  If so
I'd like to see it).  Only modern ion exchange resins can do that on
the large scale, continuously. [soapbox mode] Polymer chemistry!
[soapbox mode off].

>Anyway, a tesla system is in no part DC!!!

Ohms is still ohms.

Dunckx

* << The Ozone and water threads seem to be staying directed a little on
the subject of Tesla coils :-)  As long as the information has some
practical value it is ok. ;-)  - Terry >>