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Subject: Re: [Homebrew_PCBs] Re: HDPE container for CuCl etching?

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-08-29

On Mon, 29 Aug 2005 10:44:51 +0200, dgallavardin <dgallavardin@...>
wrote:

>
> I guess this salt can be ammonium chloride (NH4Cl)
> I stored two HCl PE bottles for about 2 years and noticed
> a thicker salt deposit on one of these bottles
> It puzzled me because these bottled were otherwise identical
> But one of them was standing near an ammonia bottle... and salt
> deposit was nearly twice as thick as the other bottle
> It easy to show: just open an hydrocholic acid and ammonia bottle
> near each other, when HCl and NH3 mix in the air it forms whitish
> NH4Cl fumes
> I guess HCl and NH3 gas can slowly diffuse through PE and form NH4Cl
> on surface.
> Deposit was seen only on hydrochric acid bottle on all the area
> This phenomemnon also shows with an HCl bottle alone as air contains
> small quantities of ammonia gas but salt growing is much slower
>


could well be...
i have ammonia containing products nearby.

ST