Pickle neutralizing - question

Folks, I had an odd occurrence last night while neutralizing my
pickle and wanted to ask about it.

Normally, I neutralize my pickle when it’s pretty depleted or weak.
This time, I had to neutralize a fairly strong/fresh batch because
I’m going out of town. I keep a separate plastic tub where I keep
a batch of 50/50 pickle and peroxide solution for firestain
removal.

When I started to neutralize the pickle/peroxide container, I
sprinkled in baking soda, but used a little more than usual and
took more time doing it than usual. It turned a beautiful clear
turquoise blue and stopped fizzing, which I’ve always taken as a
sign that it’s neutralized. But I let it sit a little longer (a
minute or two maybe?) before dumping it and all of a sudden it
started fizzing again, but the fizz was yellow and turned the
solution an opaque emerald green.

When I neutralized my pot of “just” pickle (which is in corning
ware), it didn’t do that – just turned blue and stopped fizzing.

My question, therefore is:

  • If it’s just blue does that indicate that it’s neutralized?

  • What is causing it to turn green and fizz that second time – the
    peroxide or the fact that it’s in plastic?

I should note that the plastic is a standard rubbermaid container,
never used for anything else. And the pickle acid I use is PH down
for pools and spas (which I LOVE, by the way!).

Thanks for any insights!

Karen Goeller
@Karen_Goeller
(Heading out to beautiful Annapolis MD for 4 days!)

What happened was that you threw the copper in solution into a
complex salt in two stages.

Maybe someone else can come up with the formula.

Tony Konrath
Gold and Stone
http://www.goldandstone.com

 I'm  going out of town.  I keep a separate plastic tub where I
keep a batch  of 50/50 pickle and peroxide solution for firestain
removal. 

Hi Karen, Sorry I can’t answer your question, but I’m sure you can
answer mine. Could you please explain the type of peroxide solution
you use, and how you use it? Thank you Jackie…lost in Tennessee

Hi Jackie, I keep a plastic container with a 50/50 mixture of my
regular pickle solution and hydrogen pyroxide, unheated, sitting by
my pickle pot. When a piece comes out of the pickle with any visible
copper firestaining (no matter what the metal is), I drop it in the
solution for a minute or two before washing with my regular soap and
water and it removes the firestain. Pretty foolproof unless the stain
is REALLY intense, which may require some abrasives. It’s quite
effective on brass, bronze, and sterling, and even for that uneven
red mottling you can get on copper. I haven’t tried it on gold, but
I’ve heard it works just as well, particularly if you have a
high-copper alloy.

Have fun!
Karen Goeller
@Karen_Goeller

I thought that the hydrogen peroxide degraded quickly when exposed to
air or is hydrogen pyroxide a different thing? My chemistry classes
were a l-o–n-g time ago.

Marilyn Smith

Marilyn, The hydrogen peroxide seems to retain its potency for quite
a while (several days or more) when I store it in plastic rubbermaid
container in its 50/50 pickle solution. I keep a lid on it between
working sessions to reduce evaporation, but I rarely bother making
the lid completely tight and “burped.” I’m using run of the mill
Hydrogen Peroxide that you buy in the drugstore or grocery, which
comes in those brown plastic bottles. It seems to keep in those
bottles for years, even after they are opened, which makes me think
it doesn’t degrade so rapidly – they are certainly not a special
"vacuum pack" or anything to keep the air out, particularly when
there’s only a little left in the bottle!

Karen

Hydrogen peroxide (only one spelling) has the formulae H2O2. Water
is H2O.

It degrades easily into 2(H2O2)=2(H2O)+ O2. Oxygen in bivalent - it
likes to go around in pairs - but for a short time the single atoms
are free. The oxygen is “nascent” and highly reactive. It will join
with any available material to make an oxide, copper for example ,
and if it’s in the presence of an acid the copper oxide will form a
soluble salt. That’s why it removes the pink copper flashing from the
SURFACE of a piece of sterling silver - but not the deep firescale.

Most oxides, incidentally, are white - that’s why it makes a good
bleach. It’s actually oxidizing the coloring material in hair.

Tony Konrath
Gold and Stone
http://www.goldandstone.com

    I thought that the hydrogen peroxide degraded quickly when
exposed to air or is hydrogen pyroxide a different thing? My
chemistry classes were a l-o--n-g time ago. 

I agree with Marilyn hydrogen peroxide will decompose with exposure
to light, age or even the metals in the pickle. I just add a
little from the drugstore dark bottle every time I want to soup it
up. For more see: http://www.reactivemetals.com/data/d_h2o2instr.html

Jesse