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Topic: Electrolysis of water question.  (Read 3454 times)

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Offline WhoaItsGuo

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Electrolysis of water question.
« on: February 21, 2007, 07:14:07 PM »
Hey, I've been doing electrolysis of pure water (aquafina) with potassium hydroxide (koh) added as a catalyst. I used mechanical pencil lead (graphite) for electrodes because I thought that carbon wouldn't be corroded by the highly caustic koh. Can somebody confirm that a piece of carbon metal (not graphite) will NOT interfere with the reaction (a source would be nice too)? Because the solution has to consist only of water and koh so that hydrogen and oxygen are the only products. Also, I wafted during the experiment, and my nose burned a little, which means something got out. Is this because some trace amounts (unimportant in my experiment conclusions) of koh is coming out with the hydrogen and oxygen bubbles or because something wrong is going on and some other gas is being given off? I know this post is really long. Thanks for bearing with me.

Offline eugenedakin

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Re: Electrolysis of water question.
« Reply #1 on: March 22, 2007, 12:05:56 AM »
Hello WhoaItsGuo,

You are correct.  There is probably 'something' that is coming out of solution and forming a gas.

There is a good chance that 1) the pure water, is not pure.   Read the label and see if there is any other information from the water supplier on their website. 2) the graphite from a pencil is probably not pure.  Is there any way in which you can get the lead analyzed, or the water analyzed for trace substances?

I wish you the best,

Eugene
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Offline Sam (NG)

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Re: Electrolysis of water question.
« Reply #2 on: March 22, 2007, 07:54:48 PM »
I take it that Aquafina is a bottled water and thus has many ions in solution, the gas that you inhaled was most likely contained some chlorine gas from the electrolysis of sodium chloride in the water.
« Last Edit: March 23, 2007, 04:14:48 AM by Sam-Not »

Offline Borek

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Re: Electrolysis of water question.
« Reply #3 on: March 23, 2007, 04:05:14 AM »
hydrogen chloride gas from the electrolysis of sodium chloride

Hydrogen chloride is not a product of NaCl electrolysis.
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Offline Sam (NG)

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Re: Electrolysis of water question.
« Reply #4 on: March 23, 2007, 04:14:16 AM »
Yeah, sorry, my bad. Chlorine gas.  I was drunk at the time, will teach me to post in an inebriated state.
« Last Edit: March 23, 2007, 04:21:26 AM by Sam-Not »

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