"Doug Miller" wrote in message
...
In article
,
Evan wrote:
I'm not sure if it's calcium salt, or sodium salt.


Well, its not Sodium Chloride salt, or else it would have
totally dissolved in the water...

False. Sodium chloride is not infinitely soluble in water,
and neither is
any other solid. Google "saturated solution" for an
explanation of the
concept.

CY: I'm remembering 40 grams per liter? Sound right? The
NaCL solubility doesn't vary much, with temperature.

Could be Calcium or
Magnesium...

Or it could be good old NaCl.

Not worth even worth trying to "dry it out" as the water
will have reacted with it making it a block of worthless
white powder...

Wrong again. Water doesn't react with salt, it just
dissolves it. Evaporate
the water, and you've got salt again.

CY: I remember that salt is rather ionic. Tends to break
into sodium ions, and chloride ions. But, dry it out and
it's good old salt again.

Ice control chemicals are only effective
when they are able to make their intended chemical
reactions -- your ice melter being doused with water
has chemically altered it in a way to make it useless...

Strike three. Having *anything* dissolved in water lowers
its freezing point.
Sodium and calcium salts are particularly effective at doing
this because they
dissolve easily. No chemical reaction of any sort is
involved. It's just
simple solubility.

CY: Much like glycol, or alcohol dissolves to change the
freezing point. The dissolving may be trace exothermic, I
can't remember. I remember that adding sulfuric acid to
water is exothermic.