Chemical Forums

Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: aljr on October 10, 2013, 12:31:40 PM

Title: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: aljr on October 10, 2013, 12:31:40 PM
Hello,

I'm kindly looking for some input as I was attempting to disprove the claim that combining equal parts of Ammonium Nitrate and Hydrochloric acid produces Nitric Acid once filtered.  I have read mixed information on what is chemically produced by this combination including many claiming Nitric acid to be one of the results.

Can anyone shed some light on this?
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: Hunter2 on October 10, 2013, 03:48:24 PM
You will have only a solution containing  NH4+, H+, NO3- and Cl-. But not pure nitric acid.
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: Enthalpy on October 10, 2013, 04:12:51 PM
The ammonium nitrate is in aqueous solution I hope?

Dry, it's dangerous stuff. You'd check uncompatibilities in details before pouring anything on it.
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: aljr on October 11, 2013, 09:55:29 AM
Thanks for the replies.  I performed this test in a controlled environment and the resulting formula seemed similar to Nitric Acid, but no undoubtedly a weak impure version.

I tested a small amount on 2 materials known to react with Nitric Acid, including a metal, Tin, and a epoxy plastic.  I tested reaction at room temperature and heated to 400F.  In both tests the Tin was totally dissolved into the liquid acid after approximately 2hrs, and in nether instances the plastic (also added a weak plastic strip from a pill bottle and has same result) was nit visibly altered.

Is this due to the weakness of the Acid based on the poor formula?  Anyone have suggested changes / tests that may yield different results including dissolving the epoxy plastic?
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: magician4 on October 12, 2013, 11:27:02 AM
Quote
I performed this test in a controlled environment
whaddya mean by this? diluted, waterbased solutions, or some kind of "dry NH4NO3/ conc. HCl" stuff?

because:
Quote
I tested reaction at room temperature and heated to 400F.
this is ~ 205°C, hence way above the boiling point of water, even from conc. solutions of named salts.
exposing - should it come to that - dry NH4NO3 to 200°C makes for an interesting experiment (http://en.wikipedia.org/wiki/Oppau_explosion) ...

(https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Ff%2Ff0%2FOppau_Explosion_1921.JPG&hash=d0b460da8a08b9119661bebf72e99ecdc476e2b9)
(from: http://upload.wikimedia.org/wikipedia/commons/f/f0/Oppau_Explosion_1921.JPG)

furthermore, HNO3/HCl should give some redox reaction, producing NOx , which should be voilatile in its own right...


regards

Ingo
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: 408 on October 12, 2013, 01:17:47 PM


Dry, it's dangerous stuff.

On what exactly is this statement based?


OP: Whomever told you that does not know chemistry. If you mix HCl with NH4NO3 there is no driving force towards nitric acid or HCl whether concentrated or not.  What you made is the 'poor mans aqua regia", a crude approximation of a mix of pure HCl and HNO3 made by putting a nitrate salt in HCl.  Due to the vapour pressures of both HNO3 and HCl, it is not even possible to separate these by distillation, and additionally nitrosyl chloride will be present in non-negligible quantities.

If you want nitric acid, a alkali metal nitate salt gently distilled with conc. sulfuric acid (preferably under mild vacuum) will produce pure, 100% fuming nitric. 
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: aljr on October 12, 2013, 01:26:56 PM
magician4:

As far as diluted vs dry I tested both.  The dry ammonium nitrate was crushed into a powder and had the hydrochloric acid added to it directly.  I also tested it with the ammonium nitrate dissolved in 25ml of water, and then added the HCI.

The ammonium nitrate was never dry when exposed to heat as it was always mixed with the HCI first, also with water in another test.

Boiling of the substance did occur, and gasses were released into my fume hood, but no violent explosions as your inferring.
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: Borek on October 12, 2013, 02:02:51 PM
no violent explosions as your inferring.

Lucky you. Ammonium nitrate IS dangerous. Remember April disaster in Texas?

http://en.wikipedia.org/wiki/West_Fertilizer_Company_explosion
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: 408 on October 12, 2013, 03:59:56 PM
The behavior of substances on lab scale is vastly different from tens of thousands of tons on industrial scale.  You will not be able to make ammonium nitrate detonate accidentally under lab conditions.
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: Enthalpy on October 16, 2013, 03:45:22 PM
Dry, it's dangerous stuff.
On what exactly is this statement based?

A book of two 400 pages volumes about explosives only. Put short: if mixed with a fuel, ammonitrate detonates just by ignition. If alone, it takes a detonator. Said detonator can be a portion of an ammonitrate heap that is tainted by a fuel.

Used in non-industrial amounts by fishermen. One handful in a bottle, mixed with Diesel oil, kills all fish in 100m diameter.

Heating explosives is known to ease their transition from deflagration to detonation, even in the absence of a detonator.

Having survived several similar games, I fully approve the claim by old pyrotechnicians: the more you know explosives, the more you distrust them.
Title: Re: Compound produced as result of combining Ammonium nitrate & Hydrochloric acid
Post by: 408 on October 16, 2013, 07:23:50 PM
Dry, it's dangerous stuff.
On what exactly is this statement based?

A book of two 400 pages volumes about explosives only. Put short: if mixed with a fuel, ammonitrate detonates just by ignition. If alone, it takes a detonator. Said detonator can be a portion of an ammonitrate heap that is tainted by a fuel.



Check the scale at which such issues arise.