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Author Topic: Hydrogen Peroxide  (Read 7765 times)

paul.fr

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Hydrogen Peroxide
« on: 06/03/2007 22:37:51 »
I Remember when i was younger and had a cut, my nan would insist on putting hydrogen peroxide on the cut.

She said that if it caused bubbles, it was infected with germs. not too sure now if the hydrogen peroxide then "cured" the cut or if a cream of some sort was applied.

So my question is: Why did the hydrogen peroxide bubble, i doubt it was anything to do with the presence of germs.


 

another_someone

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Hydrogen Peroxide
« Reply #1 on: 06/03/2007 22:43:09 »
I would expect hydrogen peroxide (H2O2) to bobble when it releases oxygen (2 x H2O2 -> 2 x H2O + O2).

H2O2 is fairly unstable, and will easily release O2, but what is it specifically that triggers H2O2 to disassociate in that situation I don't know.
 

Offline daveshorts

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Hydrogen Peroxide
« Reply #2 on: 07/03/2007 09:04:05 »
There are definitely enzymes to break down H2O2 in your liver, and I believe that they are also in blood, so that is probably what was breaking down the H2O2. So I would have thought that is was blood not germs making it bubble.
 

paul.fr

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Hydrogen Peroxide
« Reply #3 on: 07/03/2007 10:13:09 »
There are definitely enzymes to break down H2O2 in your liver, and I believe that they are also in blood, so that is probably what was breaking down the H2O2. So I would have thought that is was blood not germs making it bubble.

That sound about right. cheers dave
 

Offline lightarrow

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Hydrogen Peroxide
« Reply #4 on: 07/03/2007 18:29:30 »
There are definitely enzymes to break down H2O2 in your liver, and I believe that they are also in blood, so that is probably what was breaking down the H2O2. So I would have thought that is was blood not germs making it bubble.

Yes, one of them is called "Catalase".
http://en.wikipedia.org/wiki/Catalase

Detective curiosity: You want to discover quickly if a red stain on something (tissue, pavement, ecc.) is blood or something else. You put a drop of oxigenated water on it: if it makes bubbles, it's blood!
« Last Edit: 07/03/2007 18:51:00 by lightarrow »
 

Offline rosy

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Hydrogen Peroxide
« Reply #5 on: 07/03/2007 18:44:55 »
Hm, I would just point out for the benefit of people who don't know, oxygenated water doesn't necessarily mean H2O2 (that may be a perfectly legit way to refer to hydrogen peroxide but isn't one I'd met). More generally, oxygenated water is water (H2O) with molecular oxygen (O2) dissolved in it... which is not the same as hydrogen peroxide which is H2O2.
 

Offline Bored chemist

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Hydrogen Peroxide
« Reply #6 on: 07/03/2007 18:45:28 »
Since yeast also contains catalase it might be that your red stain is raspberry juice that has started to ferment. Not the sort of evidence you want to go to court with.
Human flesh, and particularly blood, are very good at decomposing peroxides- just as well since they are by products of using oxygen and they are really quite toxic.  Most of the germs that migt invade a cut will not have this protection, so hydrogen peroxide acts as a (not very) selective germicide. Probably as much use is that the bubbles tend to flush dirt out of the cut. Clean cuts heal better.
BTW, I just saw the post above. IIRC the French term for H2O2 is L'eau oxigenee (Spelling?) I guess the Itallian is similar.
« Last Edit: 07/03/2007 18:47:35 by Bored chemist »
 

Offline lightarrow

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Hydrogen Peroxide
« Reply #7 on: 07/03/2007 18:53:23 »
BTW, I just saw the post above. IIRC the French term for H2O2 is L'eau oxigenee (Spelling?) I guess the Itallian is similar.
Yes. I intended hydrogen peroxide.
 

paul.fr

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Hydrogen Peroxide
« Reply #8 on: 07/03/2007 18:59:44 »
There are definitely enzymes to break down H2O2 in your liver, and I believe that they are also in blood, so that is probably what was breaking down the H2O2. So I would have thought that is was blood not germs making it bubble.

Yes, one of them is called "Catalase".
http://en.wikipedia.org/wiki/Catalase



Catalase, that is also found in potatoes!
 

Offline Bored chemist

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Hydrogen Peroxide
« Reply #9 on: 07/03/2007 20:25:33 »
Lightarrow, What's the Italian for H2O2? (It's never going to make any real difference to me but I just wonder).
 

Offline lightarrow

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Hydrogen Peroxide
« Reply #10 on: 08/03/2007 12:42:18 »
Lightarrow, What's the Italian for H2O2? (It's never going to make any real difference to me but I just wonder).
"Acqua Ossigenata". More technically, "Perossido di Idrogeno".
 

Offline moonfire

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Hydrogen Peroxide
« Reply #11 on: 08/03/2007 20:36:49 »
LOL  I just love it when he tutors in this language
 

Offline lightarrow

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Hydrogen Peroxide
« Reply #12 on: 09/03/2007 12:32:48 »
LOL  I just love it when he tutors in this language
How it is you are so good in saying sweet things?
Hug you.
 

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Hydrogen Peroxide
« Reply #12 on: 09/03/2007 12:32:48 »

 

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