In this tutorial, I will show you how to easily make Oxygen gas with Manganese Dioxide (MnO2), and Hydrogen Peroxide (H2O2). This is one of the most common ways to make O2 in labs.
Do this experiment away from open flames and velcro (Pure O2 will ignite velcro)
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Step 1: Gather Materials...
For this experiment, you will need:
Disposable Gloves (MnO2 is stains almost anything)
Safety Goggles or Glasses
Balloon (To collect O2)
3% Hydrogen Peroxide (30% H2O2 will work a lot better but 3% is good for small amounts of O2)
Manganese Dioxide (I got mine from batteries, but you can buy it here - https://www.amazon.com/Manganese-Dioxide-Powder-Ou...)
Glass Bottle (I used an Erlenmeyer Flask but the process is the same for a soda bottle)
Step 2: Add Some Hydrogen Peroxide...
The amount of H2O2 depends on the size of your bottle/container.
I used about 50ml of H2O2.
Step 3: Add Manganese Dioxide...
Put on safety goggles/glasses.
Drop in a chunk or half a spoonful Manganese Dioxide.
It's important not to add so much that it bubbles over if you are using a soda this shouldn't be a problem.
As soon as you add the MnO2, the mixture will start to bubble O2 right away.
Alright, so what's going on here?
Hydrogen Peroxide naturally breaks down slowly over time into O2 and H2O, MnO2 catalyzes the breakdown and increases it significantly. The chemical equation is - 2H2O2——MnO2—→2H2O+O2.
Step 4: Capture O2!...
After the solution starts bubbling, quickly and carefully place a balloon over the rim of your bottle.
The balloon will fill with pure Oxygen gas.
The bubbling will stop rather quickly because there is only 3% H202 in a solution of water. If you want more O2 you should use 30% Hydrogen Peroxide, keep in mind that 30% is dangerous and can burn/blind you.
When you are done, you can pour the MnO2 mixture down the drain and wash and keep your bottle for future use.
Step 5: Hold Oxygen...
I found the best way to temporarily hold the O2 without tying was to wrap the end of the balloon twice over a clothes clip.
This will hold while you get an O2 test ready!
Step 6: Test for Oxygen...
A very easy test for Oxygen Gas is to light a splint of wood, blow it out, then stick it into/blow O2 on to it, if the splint was still red hot, it should reignite, showing the presence of Oxygen.