# Why does (or "do"?) Barium Oxide + Sulfuric Acid yield Ozone?

## From my textbook: The texbook says that if you pre-cool the test tubes with the initial components in the snow, you'll get some ozone. But why ozone and not just ${O}_{2}$?

Feb 14, 2016

Here's what I got.

#### Explanation:

Ok, now this is a very interesting question.

First thing first, the reaction involves barium peroxide, ${\text{BaO}}_{2}$, not barium oxide, which is $\text{BaO}$.

Now, as far as I know, this reaction is used to produce hydrogen peroxide, ${\text{H"_2"O}}_{2}$.

If you plan on using dilute sulfuric acid, you should use barium peroxide octahydrate, $\text{BaO"_2 * 8"H"_2"O}$. The reason behind this is that barium sulfate, ${\text{BaSO}}_{4}$, which is an insoluble ionic compound, forms on the surface of the peroxide, essentially halting the reaction.

Also, the reaction is performed with an ice-cold acid solution because the low temperature slows down the decomposition of hydrogen peroxide to water and oxygen gas.

$2 {\text{H"_2"O"_text(2(aq]) -> 2"H"_2"O"_text((aq]) + "O}}_{\textrm{2 \left(g\right]}} \uparrow$

The balanced chemical equation for when this reaction (I'll use anhydrous barium peroxide for the sake of simplicity) is performed at low temperature looks like this

${\text{BaO"_text(2(s]) + "H"_2"SO"_text(4(aq]) -> "BaSO"_text(4(s]) darr + "H"_2"O}}_{\textrm{2 \left(a q\right]}}$

At room temperature and catalyzed by potassium iodide, $\text{KI}$, this reaction should proceed like this

$2 {\text{BaO"_text(2(s]) + 2"H"_2"SO"_text(4(aq]) stackrel(color(red)("KI")color(white)(aa))(->) 2"BaSO}}_{\textrm{4 \left(s\right]}}$ $\downarrow + 2 {\text{H"_2"O"_text((aq]) + "O}}_{\textrm{2 \left(g\right]}} \uparrow$

So my guess is that this reaction will produce ozone as a side product, maybe depending on a combination of catalyst, reaction temperature, and concentration of the acid.

I was able to find a YouTube video on this supposed reaction - the narration and the subtitles are in Russian, so that will not be very helpful to students who don't speak it.