
Hydrogen peroxide (H2O2) is a common bleaching agent available at most drugstores. The bottle typically contains a 3% solution, meaning 97% of it is water, with only 3% being hydrogen peroxide. It's primarily used as an antiseptic.
Although hydrogen peroxide isn't the best antiseptic, it's still useful for cleaning cuts and scrapes, and the foam it produces is certainly intriguing. But why does hydrogen peroxide bubble up? Let's break down the science behind the foamy reaction.
What Is Hydrogen Peroxide?
Hydrogen peroxide is fundamentally a simple chemical compound, though its formula is a bit more intricate: H2O2. This shows that it’s made up of two hydrogen atoms (H) and two oxygen atoms (O).
Understanding the Hydrogen Peroxide Fizz
The bubbling occurs because both blood and cells contain an enzyme called catalase. When you have a cut or scrape, these components are present in abundance, providing plenty of catalase.
When catalase interacts with hydrogen peroxide, it breaks it down into water (H2O) and oxygen gas (O2), which causes the foaming effect.
Catalase is incredibly effective in catalyzing reactions, with the ability to process up to 200,000 reactions per second. When it comes in contact with hydrogen peroxide, it causes the formation of oxygen bubbles due to its catalytic action.
If you apply hydrogen peroxide to a cut potato, the same reaction occurs. This happens because the catalase present in the damaged potato cells interacts with the hydrogen peroxide, producing oxygen bubbles.
Why Doesn't Hydrogen Peroxide Bubble in the Bottle?
Hydrogen peroxide does not bubble when stored in a bottle or when it interacts with healthy cells because there is no catalase present to facilitate the reaction. At room temperature, hydrogen peroxide remains stable.