[Cupro Chlorous]

Well, I'm attempting to make Hydrochloric Acid the industrial way at home.

Through the electrolysis of a Brine Solution, Chlorine Gas and Hydrogen are released.

I once tryed to collect these gasses, that didnt work to well however.  Anyway,if i simply bring H₂ and Cl₂ together, will they react?

[Mitch]

It'll probably explode and spray your precious HCl in your eyes and all over your clothes.

[Cupro Chlorous]

I see.  Best to avoid this altogether then!

Usually, chlorine is released for the first 15 minutes or so, and by that time the sodium hydroxide is concentrated enough to absorb the chlorine before it comes out.  I have not had any explosions thus far.

[jdurg]

I see.  Best to avoid this altogether then!

Usually, chlorine is released for the first 15 minutes or so, and by that time the sodium hydroxide is concentrated enough to absorb the chlorine before it comes out.  I have not had any explosions thus far.

Chlorine and Hydrogen is somewhat similar to Oxygen and Hydrogen.  If you don't have a high enough concentration or an intimate enough mixing nothing much will happen.  The troubling thing is that while hydrogen and oxygen require a spark or ignition source in order to get going, hydrogen and chlorine do NOT.  The Cl-Cl bond is pretty weak and the Chlorine molecules are easily broken apart into free radicals.  These radicals rapidly attack the hydrogen molecules and provide enough energy to break apart other chlorine molecules and form more HCl.  This leads to a chain reaction commonly known as an explosion.  The amount of energy needed to get this reaction going is so small that simple visible light in the blue end of the spectrum is enough to set it off.  If a test tube filled with equal parts H2 and Cl2 is stoppered in a dark room, if you shine a blue light onto the tube, it will explode.  

[woelen]

In fact, this is a nice demo I did once. I made H2 by adding magnesium to HCl. Collected in a little test tube. I also made Cl2 and collected this in a separate test tube. I mixed the two in small quantities (just a few ml) and bubbled this in soap water. I mixed appr. 2 parts of Cl2 with 1 part of H2. This is necessary, because when the mix bubbles through water, part of the Cl2 dissolves. In that way your bubbles will be close to a 1:1 mix of H2 and Cl2. Next, take a photography flash light and trigger the flash. At the moment you have the flash, there also is a loud BOOM. Be careful, not to have any H2 : Cl2 mix in a glass bottle or test tube, when the flash occurs, or you'll regret it.

[billnotgatez]

What would be the best method of preparing hydrochloric acid in the home laboratory? For the sake of argument exclude going out and buying it.

[jdurg]

What would be the best method of preparing hydrochloric acid in the home laboratory? For the sake of argument exclude going out and buying it.

Take some simple table salt (NaCl) and drop some concentrated (>-98%) H2SO4 on the anhydrous salt.  Collect the vapors that arise from the salt (HCl) into a container filled with water and you'll have HCl.

[billnotgatez]

What would be the best method of preparing concentrated (>-98%) H2SO4 in the home laboratory? For the sake of argument exclude going out and buying it.

[Mitch]

98% H2SO4 doesn't exist. If it did, you would probably die from the fumes.

[Borek]

98% H2SO4 doesn't exist.

Huh? Too much work on the search boxes lately?  

[Mitch]

Apparently Fisher does sell it. Odd, I thought no one did. oh-well.

[jdurg]

Apparently Fisher does sell it. Odd, I thought no one did. oh-well.

That's pretty much the standard concentration of "concentrated" sulfuric acid.  It's the 100% H2SO4 that isn't really available as the fumes from that stuff would not be something I'd want to be around.  (Then again, being around 98% H2SO4 isn't too much fun either).

[Borek]

I am more then sure that you should be able to buy 'overconcentrated' stuff - fuming sulfuric acid? - with something like 60% SO₃ dissolved.

[woelen]

Yes, Oleum, consisting of 65% SO3 by weight and 35% H2SO4 is available commercially. Unfortunately I have not found a source who sells it to individuals , nor can it be made easily at home. I really would like to have some of that stuff. It can be used for really neat experiments (such as making salts of iodine as cation, or making nitroso salts). And yes, I know the dangers of this stuff  .

[limpet chicken]

Actually, it isn't too difficult to prepare oleum, pyrolysis of ferrous sulfate decomposes it to SO3, if one already has concentrated H2SO4, then passing the sulfur trioxide fumes through it, carefully of course, is all it takes.

Of course, it must be handled damn carefully, as it fumes like the coals of hell, and it burns skin FAST, I still have some faded scars on the back of my hand from my first time using some fuming H2SO4 I had prepared not an hour or two earlier, the experiment in question, involved strongly heating the H2SO4, which spat, and landed on my hand, went straight through my fairly thick leather gloves, and decided to promply dehydrate my tender young flesh.