# Hydrochloric acid

Discussion in 'Chemistry' started by Extrovert39, Jun 15, 2012.

1. ### Extrovert39Registered Member

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If HCl is poured into water (H2O), what is produced?

3. ### BelieveHappy mediumValued Senior Member

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Pure 100% HCl is a gas so the liquid HCl you have there is HCl already dissolved in H2O. Adding more water to it will just dilute it. You also get ions I suppose H^+ and Cl^-.

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H3O+ and Cl-

7. ### Extrovert39Registered Member

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Is Nasor correct?

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9. ### Extrovert39Registered Member

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So Cl- is given off as a gas? Is it possible to mix Cl- with H20?

Thanks for the big help guys.

10. ### originTrump is the best argument against a democracy.Valued Senior Member

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Cl- is an ionic solid. Cl2 is a gas and a very nasty gas. You will not get Cl2 the only gas will be H2

When you add acid to water a reaction occurs because you are effectively adding a very low pH liquid to a high pH liquid. The reaction is very exothermic, so much so that adding water to a high molality acid could cause the water to instantly boil and splash into your face - a bad deal.

That is why you should:

"add acid to wata (water) like you outa (ought to)".

Never add a water to acid.

By the way, saying you get Cl- and H+ or saying you get Cl- and H3O+ amounts to the same thing.

11. ### BelieveHappy mediumValued Senior Member

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Yes and no we are both right. It is in a state of constant flux between H3O (hydronium) and H+. Most of the mechanisms that I have studied just list it as H+ so I generally just list it as H+ but both are equally correct!

Last edited: Jun 16, 2012
12. ### BelieveHappy mediumValued Senior Member

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I'm not sure if this is really a problem with HCl as it is already diluted. I think you can only get it at like 35% purity as in a pure state it is a gas but good advice none the less! However, with nitric acid and ESPECIALLY sulfuric acid this is very true. Never, ever add water to pure sulfuric acid or you're gonna have a bad time.

13. ### BelieveHappy mediumValued Senior Member

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No gas, the Cl- is an ion in the water still so it is mixed with the H2O. Likely it causes the H2O to form some OH- and it goes back to HCL but not very much as the OH- would almost instantly combine with one of the free H+ ions or a H3O to make 2 H2O's since the solution is acidic. Most things like this (water included) actually exist in a state of flux called an equilibrium state. Chemistry is fun! To learn more about the self ionization of water read this:

http://en.wikipedia.org/wiki/Self-ionization_of_water

14. ### Extrovert39Registered Member

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I'm looking to make H30+. I thought HCl in water might do this, but sounds like maybe not. Any ideas?

15. ### originTrump is the best argument against a democracy.Valued Senior Member

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It will make H3O+

HCl -> (in water) Cl- + H+.

H2O + H+ <--> H3O+

'Making' some sort of stable H3O is not really possible because the proton (H+) bounces around from water molecule to water molecule and it floats around the solution on it's own too.

16. ### Extrovert39Registered Member

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Would the h+ ions escape the hydronium solution to crate just water?

I need to make just H30+ Lol...

Also is it possible electricity would conduct over the H+ ions? I wonder if a current would turn it into H20 because the H+ would combine with oxygen in the air...

17. ### originTrump is the best argument against a democracy.Valued Senior Member

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Water breaks apart and recombines in the following manner.

$H_2O <-> OH^- + H^+$.

So the water is in an equilibrium of the disassociation and recombination of the hydroxyl and hydronium ions into water, chemically it is described with an equilibrium constant:

$K = \frac{[H^+] [OH^-]}{[H_2O]}$

K tells you to what level the water disassociates.

The amount of disassociation in pure water is low though ~ $1 X 10^{-7}$ for $OH^-$ and $1 X 10^{-7}$ for $H^+$.

pH is the negative log of the $H^+$ ion. So bascially this tells you that if you decrease the pH (add acid) you are increasing the concentration of the $H^+$.

The $H^+$ can also be expressed as $H_3O^+$.

If you want a conductive solution the use of salt would be much easier and safer.

18. ### Extrovert39Registered Member

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Thanks for the info.

All I really want to be sure of now (I've understood everything else) is that HCl in water will create hydronium. The hyndronium won't break down, there won't be tons of other stuff in it. We need it for our lab

...will keep ya'll posted.

We'll also be interested in the conductivity, maybe H30+ will be a mediocre conductor.

19. ### originTrump is the best argument against a democracy.Valued Senior Member

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Pure water is a terrible conductor. The more HCl you add the more conductive the water will be because of the H+ and the Cl-.

20. ### NasorValued Senior Member

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You can make solid crystals of hydronium and a counter-anion, although I don't think any of them are very safe to make or handle.

21. ### Extrovert39Registered Member

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We're going to give it a shot with Muratic acid from the hardware store.

There is muratic acid, and a "substitute". There are no ingredients lists, however both say they contain hydrochloric acid.

How do the "water it down" if HCl will react with water to produce hydronium and chloride?

With muratic acid, will we get hydronium, or something else, or possibly crap in there?

22. ### NasorValued Senior Member

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What exactly are you trying to do?

23. ### BelieveHappy mediumValued Senior Member

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The muratic acid is already HCl + H2O, as is all liquid HCl since pure HCl is a gas. So you already have hydronium and H+. Adding more water will just dilute it.

BTW, I hope you are not trying to make meth or something.