How many ppm of O2 does H2O2 add to water?

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The discussion centers on raising the dissolved oxygen content in distilled water from zero to 10 ppm using a 6% hydrogen peroxide (H2O2) solution. It clarifies that 10 ppm does not equate to 10 molecules but rather a concentration of 10 mg/L. The decomposition of hydrogen peroxide generates oxygen, with the kinetics of this reaction influenced by other substances present. A calculation reveals that to achieve 10 ppm of oxygen, approximately 0.33 grams of hydrogen peroxide is needed, considering a yield of about 47% from the decomposition reaction. It is suggested to dilute the hydrogen peroxide further for accurate measurement due to the small quantity required. Additionally, it is noted that if the water is exposed to the atmosphere, it will naturally absorb some oxygen, and boiling the water can help remove this dissolved oxygen. The conversation also mentions products like Clean&Clear and Oxysept, which utilize catalysts to decompose hydrogen peroxide efficiently, producing oxygen rapidly.
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Trying to work out how to raise the oxygen ppm of a litre of water by a measure quantity using hydrogen peroxide.
I'm starting with a litre of distilled water with a dissolved oxygen content of zero ppm, and I wish to raise the ppm of the dissolved O2 to 10ppm or 10mg/L using a 6% solution of H2O2. That is 10 extra molecules of oxygen in a litre!

I've had no luck looking for through web based conversion calculators and other technical papers. So I am reaching out here hoping that someone can explain the correct way to calculate this.

thanks in advance.
 
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bland said:
That is 10 extra molecules of oxygen in a litre!
No, 10 ppm doesn't mean 10 molecules.

Technically adding hydrogen peroxide you don't add oxygen, oxygen will be produced when the hydrogen peroxide decomposes - which takes time. Kinetics of the process will be a nightmare to describe, as it depends on other dissolved substances catalyzing the reaction.

What you can do is to calculate amount of oxygen that will be produced from the introduced hydrogen peroxide (rather simple stoichiometry), that will help you estimate maximum possible concentration of oxygen after the decomposition (with assumption none of the produced oxygen runs out).
 
I wanted to work this out just for fun as I am not a real chemist. Molar Mass of hydrogen peroxide is 34, and of oxygen 32. The reaction is 2 H2O2 gives O2. So 68g of hydrogen peroxide give 32g of oxygen, a yield of 32/68 x100=47%.
To provide 10ppm in 1 litre of water will require 1000 x 10^-5 = 10^-2 g of oxygen. This will require (10^-2) x 100/47 = 0.02 g of hydrogen peroxide. Using a 6% solution will require 0.02 x 100 / 6 = 0.33g of hydrogen peroxide.
As this is a very small amount to measure, maybe dilute the hydrogen peroxide a further ten times before measuring the dose.
 
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tech99 said:
This will require (10^-2) x 100/47 = 0.02 g of hydrogen peroxide.
OK
tech99 said:
Using a 6% solution will require 0.02 x 100 / 6 = 0.33g of hydrogen peroxide.
Of the hydrogen peroxide solution, to be precise :smile:
 
tech99 said:
I wanted to work this out just for fun as I am not a real chemist. Molar Mass of hydrogen peroxide is 34, and of oxygen 32. The reaction is 2 H2O2 gives O2. So 68g of hydrogen peroxide give 32g of oxygen, a yield of 32/68 x100=47%.
To provide 10ppm in 1 litre of water will require 1000 x 10^-5 = 10^-2 g of oxygen. This will require (10^-2) x 100/47 = 0.02 g of hydrogen peroxide. Using a 6% solution will require 0.02 x 100 / 6 = 0.33g of hydrogen peroxide.
As this is a very small amount to measure, maybe dilute the hydrogen peroxide a further ten times before measuring the dose.

Okie dokie that is some decent ball park figures to work with, it is indeed a small quantity. thanks.
 
If your water is open to the atmosphere, then a small amount of air (mostly nitrogen, but about 19% oxygen) will dissolve in the water. To remove it, you will need to boil the water. That also makes it sterile (until the air re-dissolves into the liquid). For fun, buy Clean&Clear or Oxysept used for dis-infecting contact lenses. C&C uses a platinum disc (catalyst) to decompose the H2O2 to water. Oxysept uses catalase, an enzyme, with a pink indicator to decompose the H2O2 to water. You can see the Oxygen bubbling out almost immediately. Process to convert all H2O2 to plain water requires 6 hours. I am a chemist and a contact lens wearer.
 
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