This experiment is for advanced students.

In industry, hydrogen peroxide is used in paper making to bleach the pulp before they form it into paper. Biologists, when preparing bones for display, use peroxide to whiten the bones.

At home, 3% peroxide combined with ammonium hydroxide is used to give dark-haired people their desired blonde moment. Peroxide is also used on wounds to clean them and remove dead tissue. Peroxide slows the flow from small blood vessels and oozing in wounds as well.

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Peroxide is a chemical produced in a Bombardier Beetle, and it squirts its irritating load into the face or onto the lips of a predator. Zebra fish produce peroxide after their skin is damaged. This action acts as a signal to produce an abundance of white cells to fight any infection and assist in the healing.

Scientists believe that healing can occur in humans in the same way. Future experiments may prove them right. It is also believed that people who have asthma have elevated levels of peroxide in their lungs, levels much higher than people without asthma.

Hydrogen peroxide can also help an animal that has eaten poison. A small amount of it can be put down the animal’s throat to induce vomiting and clear the poison out of their body as much as possible. Did your dog get too close to a skunk? There is no real “cure” other than a lot of time outside to air out, but peroxide mixed with hand soap is pretty good at removing the stink. Then, how you remove that stink from yourself…..another problem.

Materials:

• 2 test tubes
• Burner
• Lighter
• Chemistry stand
• Test tube holder
• Glass jar
• Water pan
• Water
• Rubber tubing
• 90^o glass tubing
• 3% Hydrogen peroxide (H₂O₂) (MSDS)

Hydrogen peroxide comes in a dark bottle because sunlight will slowly decompose hydrogen peroxide in the same way that we are doing with the exception that our way is much quicker.

When finished heating hydrogen peroxide, if you leave everything together, water will climb the tubing and attempt to enter the hot test tube. Cold water and hot peroxide are not safely compatible. To avoid this, remove the stopper from the test tube and set it aside while the solution cools.

Wait until all the equipment is cool enough to touch before disassembling for cleaning and storage.

When heating the test tube, be careful. Don’t heat in one place for too long. Move the flame of the burner around periodically to heat the reaction area of the test tube uniformly.

Don’t boil the peroxide too vigorously. If boiling gets too wild, remove the burner form the test tube until it calms down, then move it back to heat again.

At all times, keep the flame and peroxide apart…well apart.

Hydrogen peroxide is going to get broken down, is going to decompose, into the base elements of hydrogen and oxygen.

Download Student Worksheet & Exercises

Here’s what’s going on in this experiment:

Hydrogen peroxide (H₂O₂) breaks down with heat. A decomposition reaction occurs where hydrogen peroxide breaks down into its component elements, H₂ and O₂

2H₂O₂ –> 2H₂O + O₂

2 molecules of hydrogen peroxide are heated, creating a chemical decomposition reaction, producing 2 molecules of water and 1 molecule of oxygen.

Cleanup: Clean everything thoroughly after you are finished with the lab. After cleaning with soap and water, rinse thoroughly. Chemists use the rule of “three” in cleaning glassware and tools. After washing, chemists rinse out all visible soap and then rinse three times more.

Storage: Place cleaned tools and glassware in their respective storage places.

Disposal: Liquids can be washed down the drain

Going further: Elephant’s Toothpaste

A really fun experiment with hydrogen peroxide is making Elephant’s toothpaste. It requires an adult helper, and is fun for the kid and the adult.

Materials:

• Empty 20 or 24 ounce plastic bottle
• 3 % hydrogen peroxide
• Liquid dish soap
• Warm water
• Food coloring
• One packet or 2 1/2 ounces of yeast
• One really big container to contain the big mess – laundry tub, bathtub, etc.

This video below is a demonstration of the Elephant Toothpaste experiment using much nastier chemicals than the ones I’ve mentioned above… the hot gas generated is actually oxygen. Enjoy!

Procedure:

• Dissolve the yeast in a little warm water and stir well.  Use just enough water to make a pourable liquid.  Let it sit for about 5 minutes while you prepare the rest of the experiment.
• Pour 1/2 cup of hydrogen peroxide, 1/4 cup of dish soap and a little bit of food coloring in the bottle.  Swirl to mix and put the bottle in the middle of your large pot, container or sink.
• Pour the yeast solution into the bottle.  A funnel can help, but be prepared to pour fairly quickly and remove it again because the reaction will start as soon as you start pouring.
• Stand back and watch the fun!

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