On Sep 27, 2:17 pm, Joe Sallustio > wrote:
> So> my couple of pounds of reagent should last me for about another
> > century or so of winemaking, assuming I keep it dry. :-)
>
> That is the key, it's hygroscopic. I have a friend who is a chemist
> and he said that was it's biggest drawback, it sucks in moisture like
> a sponge...

It will not only absorb moisture, it will also suck up carbon dioxide
from the air to form sodium carbonate. That will also throw all of
your calculations off.

You could, however, standardize your solution by testing the amount of
acid in a known mass of tartaric acid, and fix your calculations that
way.