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Make hydrochloric acid

  1. Feb 12, 2005 #1
    I was thinking about make some HCl. My idea was to electrolys a NaCl solution and get a solution of H2 and Cl2. Then ignite the solution, which reacts and becomes HCl. Then I'll solute the gas in water.

    Will it work?
  2. jcsd
  3. Feb 12, 2005 #2


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    I certainly wouldn't recommend it, for the following reasons :

    1. The electrolysis itself is not trivial. You will need an adjustable 0-5V DC supply to get the right bias voltage.

    2. The collection of the gases will be difficult. Hydrogen is a dangerous gas...it blows the hell up if activated in the presence of air. If you have any hydrogen floating around when you throw a switch (for instance, the one on your power supply), you are essentially setting off a bomb.

    3. Chlorine is heavier than air (you will have to collect it over water, but it is partially soluble in water - coincidentally, making a very weak solution of HCl)), and poisonous. You do not want to risk ihnhaling it. If some leaks out of your collection system, it doesn't float away very fast.

    4. Chlorine doesn't just "react" with hydrogen, it explodes. Like many other photochemical chain reactions, it is very tricky to control the rate of reaction.

    My advice : please do not attempt this.
  4. Feb 12, 2005 #3
  5. Feb 13, 2005 #4
    Hmm. Ok. I'll figer out something else...
  6. Feb 14, 2005 #5
    If you carry out it in a more dimmer place, it will be less explosive but I've never tried./
  7. Feb 20, 2005 #6
    You'll mostly get a sol'n with hypochlorite and chlorate, and not much Cl2 gas being evolved. Chlorine is soluble in water, where it forms HOCl. That in turn decomposes to form ClO3-. The standard way of making hydrochloric acid in the lab is to heat a chloride with H2SO4 and dissolve the HCl gas in H2O.
  8. Feb 12, 2007 #7
    I think if you were to do it in a dimmer place, youd just not be able to see when you blow your fingers off
  9. Feb 13, 2007 #8


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    Although your method would, technically work, it would neither be safe nor a practical method of producing HCl.

    There are alternative methods, however.
    Some chemical reactions will give off HCl gas as a product. If you collect this gas a bubble it through water to dissolve it, you will obtain an HCl solution (and if you do it right, you won’t have to breathe any harmful vapors).
    One such reaction is,
    NaCl + H2SO4 --> Na2SO4 + HCl
    Involving Sulfuric acid to produce Hydrogen Chloride from NaCl.

    But making it yourself (as satisfying as it may be) is overly troublesome when you can go down to the hardware store and pick up a gallon jug of ~35% HCl (aq) for under $10. Much safer and a higher quality product.
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