[josephusflav]

Im trying to refute holcaust denial.

There is a argument that goes "delousing areas of the camps have blue stains, a result of zyklomb b. The death rooms dont have the stains therefore no holocaust"

Wikipedia refutes this

"The problem with Prussian blue is that it is by no means a categorical sign of cyanide exposure.[4] One factor necessary in its formation is a very high concentration of cyanide.[4] In terms of the difference between amounts measured in the delousing chambers and homicidal gas chambers, critics explain that the exact opposite of what deniers claim is true. Insects have a far higher resistance to cyanide than humans, with concentration levels up to 16,000ppm (parts per million) and an exposure time of more than 20 hours[5] (sometimes as long as 72 hours) being necessary for them to succumb. In contrast, a cyanide concentration of only 300ppm is fatal to humans in a matter of minutes.[6] This difference is one of the reasons behind the concentration disparity. "


The problem I see when using this it seems some "gentlemen"  might try to say

"If it takes more cyanide to kill bugs than people then people should die if there deloused."

The answer to that claim is likely too be found in some chemistry mumbo jumbo.

Sadly I dont know that mumbo jumbo is,

please help

[Arkcon]

Im trying to refute holcaust denial.

We're glad to help, but this is, to some extent, a Fool's Errand.  People who form such opinions are often unreachable with polite, factual debate.  Likewise, YEnCers, or Flat Earthers.

There is a argument that goes "delousing areas of the camps have blue stains, a result of zyklomb b. The death rooms dont have the stains therefore no holocaust"

And some Holocaust deniers have even identified that some bricks are discolored with the prussian blue product.  So you can claim whatever you want with selective evidence.

Wikipedia refutes this

Yes it does.  See here: https://en.wikipedia.org/wiki/Zyklon_B#Use_in_the_Holocaust

Holocaust deniers claim that Zyklon B gas was not used in the gas chambers, relying for evidence on the research of Fred A. Leuchter, who found low levels of Prussian blue in samples of the gas chamber walls and ceilings. Leuchter attributed its presence to general delousing of the buildings. Leuchter's negative control, a sample of gasket material taken from a different camp building, had no cyanide residue.[61] In 1999, James Roth, the chemist who had analyzed Leuchter's samples, stated that the test was flawed because the material that was sent for testing included large chunks, and the chemical would only be within 10 microns of the surface. The surface that had been exposed to the chemical was not identified, and the large size of the specimens meant that any chemical present was diluted by an undeterminable amount.[62] In 1994, the Institute for Forensic Research in Kraków re-examined Leuchter's claim, stating that formation of Prussian blue by exposure of bricks to cyanide is not a highly probable reaction.[63] Using microdiffusion techniques, they tested 22 samples from the gas chambers and delousing chambers (as positive controls) and living quarters (as negative controls). They found cyanide residue in both the delousing chambers and the gas chambers but none in the living quarters.[64]

"The problem with Prussian blue is that it is by no means a categorical sign of cyanide exposure.[4]

One factor necessary in its formation is a very high concentration of cyanide.[4] In terms of the difference between amounts measured in the delousing chambers and homicidal gas chambers, critics explain that the exact opposite of what deniers claim is true. Insects have a far higher resistance to cyanide than humans, with concentration levels up to 16,000ppm (parts per million) and an exposure time of more than 20 hours[5] (sometimes as long as 72 hours) being necessary for them to succumb. In contrast, a cyanide concentration of only 300ppm is fatal to humans in a matter of minutes.[6] This difference is one of the reasons behind the concentration disparity. "

The above quote is a better one, but we can use this one as well.  Zyklon B was a fumigant, we still use fumigants, for example ethylene oxide.

The problem I see when using this it seems some "gentlemen"  might try to say

"If it takes more cyanide to kill bugs than people then people should die if there deloused."

Yes.  Zyklon B or ethylene oxide in my example, aren't delousers, they're fumigants.  They can kill humans before they kill insects or microbes in the case of ethylene oxide.  That's why they're used in sealed chambers, and ventilated afterward.

The answer to that claim is likely too be found in some chemistry mumbo jumbo.

Sadly I dont know that mumbo jumbo is,

please help

With the caveats I mentioned at the start of this thread, I believe you have something you can work with now.

[chenbeier]

Additional. Zyklon B was Hydrogencyanide adsorbored on diatomaceous earth and lime. Used as pellets it releases gas. The absence of prussic blue has nothing to do I think. Prussic blue needs iron and alkaline conditions. So obtained by cooking meat and skins from animals with iron powder and potassium carbonate. Historically, the compound was manufactured from organically derived nitrogenous carbon sources, iron filings, and potassium carbonate. Common nitrogen and carbon sources were torrified horn, leather scrap, offal, or dried blood.
The HCN gas alone cannot create pussic blue.

[Arkcon]

Additional. Zyklon B was Hydrogencyanide adsorbored on diatomaceous earth and lime. Used as pellets it releases gas. The absence of prussic blue has nothing to do I think. Prussic blue needs iron and alkaline conditions.

The bricks and stone of the chambers could have iron impurities.  Also iron and steel parks in the areas as well.  Notably, I've never heard anyone conform or deny that the pipes and spray heads, which I assume a iron, are or are not coated with the tell-tale blue color of Prussian blue.  Again, this is selectively used evidence, used by different people, in different ways, to prove and disprove the same points.

So obtained by cooking meat and skins from animals with iron powder and potassium carbonate.

Uh ... interesting bit of trivia.   I believe that organic and inorganic synthesis was well developed, in Germany, by this point in time.  So not really relevant.

More trivia: development of early Zyklon formulations was done by Fritz Haber, a scientist who worked for Germany's war effort in World War I.  His Noble prize was contested by French and British, for his war efforts against them.  He was not yet thrown out of Germany, for being Jewish, but would be, before his death.

https://en.wikipedia.org/wiki/Zyklon_B#History

https://en.wikipedia.org/wiki/Fritz_Haber

Historically, the compound was manufactured from organically derived nitrogenous carbon sources, iron filings, and potassium carbonate. Common nitrogen and carbon sources were torrified horn, leather scrap, offal, or dried blood.

Not at this point in time.

The HCN gas alone cannot create pussic blue.

I really don't know the reactions involved.  As a kid, I easily made Prussian blue with ferric ammonium sulfate and potassium cyanate.  But those are soluble salts and the reaction is in aqueous solution.  Some bricks show blue color outside the chambers, or only on parts on the inside.  This is very muddled chemistry, and very, politically muddled, forensic science. 

I don't think its really worth working on, given what I said at the start of this thread.