Was: Forgot ring in pickle
I appreciate the thought behind the idea of weak pickle being a
safety device. The problem is my little brain seems to remember a
time when I used to teach chemistry. I seem to remember that in some
cases using a dilute acid actually made it more potent, this might
only be true of a few acids however. Some dilute acids ionize more
than more concentrated solutions. I am not talking about acids so
concentrated they are fuming, but so concentrated that the water does
not ionize the acid as well as it would with a more dilute solution.
A bit weird - weaker = stronger. I have found this to be true with
nitric acid and aluminum where a weaker solution will work where a
stronger one does not (there are oxidizing actions at work here to
confound things). The same oddity seems to happen with some of the
sulfuric acid salts.
Be that as it may, I have also begun to “stifle” myself and not
quench my hot silver in the pickle. I have never proven the following
two reasons beyond a doubt, but there is some evidence to support my
guesses. First, quenching in hot pickle seems to entrap some of the
acid in the “open” pores. Might be black magic, but I seem to have
better luck on subsequent operations if I quench in water first. I do
love the way the oxides vanish with the hot acid quench however. The
other issue which concerns me personally a bit less is the idea that
you volatilize or boil off some of the acid salt when you hot quench
- rusting tools and rotting lungs.
How do the rest of you deal with the hot quench issue?