Explosive foam
You really need a proper science lab and a trained presenter to do this experiment. It is more of a demonstration than a participatory exercise.
Ingredients
- A tub which holds about 1 gallon
- Water
- Soap
- A beaker or test tube
- A stopper with a hole
- Glass elbow and rubber tubing
- Hydrochloric acid
- Magnesium ribbon
- A lighter
What to do
- Step 1: Fill the tub with very soapy water
- Step 2: Fill the beaker or test tube about half way with hydrochloric acid
- Step 3: Attach the glass elbow and the hose to the stopper
- Step 4: Place the other end of the hose in the tub of soapy water
- Step 5: Add a small amount of the magnesium ribbon to the beaker and quickly cover the top with the stopper; hold the beaker so it is lower than the tub and there are no kinks in the hose
- Step 6: Bubbles will appear in the tub
- Step 7: Pick up some bubbles with your hand and light them with the lighter; they should go up quite spectacularly without burning your hand
- Step 8: When you get tired of playing with the bubbles, you can light the ones left in the tub all at once. FWOOSH!
Principle
Magnesium and hydrochloric acid react to create hydrogen gas and magnesium chloride. The chemical equation looks like this:
Mg (s) + 2HCl (aq) –> H 2 (g) + MgCl 2 (aq)
Because Hydrogen gas is lighter than air, it travels up the tube and bubbles through the water. Hydrogen gas burns at a relatively low temperature and shouldn’t harm your hand when you light it.
Written for younger readers
Explosive foam, in simpler words
This version comes from Wikijunior, a set of books written for children aged 8 to 11. It is shorter and uses plainer language than the article above.
From Wikijunior: Big Book of Fun Science Experiments
You really need a proper science lab and a trained presenter to do this experiment. It is more of a demonstration than a participatory exercise.
A tub which holds about 1 gallon
Water
Soap
A beaker or test tube
A stopper with a hole
Glass elbow and rubber tubing
Hydrochloric acid
Magnesium ribbon
A lighter
Step 1: Fill the tub with very soapy water
Step 2: Fill the beaker or test tube about half way with hydrochloric acid
Step 3: Attach the glass elbow and the hose to the stopper
Step 4: Place the other end of the hose in the tub of soapy water
Step 5: Add a small amount of the magnesium ribbon to the beaker and quickly cover the top with the stopper; hold the beaker so it is lower than the tub and there are no kinks in the hose
Step 6: Bubbles will appear in the tub
Step 7: Pick up some bubbles with your hand and light them with the lighter; they should go up quite spectacularly without burning your hand
Step 8: When you get tired of playing with the bubbles, you can light the ones left in the tub all at once. FWOOSH!
Magnesium and hydrochloric acid react to create hydrogen gas and magnesium chloride. The chemical equation looks like this:
Mg (s) + 2HCl (aq) –> H 2 (g) + MgCl 2 (aq)
Because Hydrogen gas is lighter than air, it travels up the tube and bubbles through the water. Hydrogen gas burns at a relatively low temperature and shouldn’t harm your hand when you light it.
Where this page comes from
The article above is adapted from “Explosive foam” on Simple English Wikipedia, by its contributors. We removed reference markers, navigation boxes and tables, expanded measurement templates into readable numbers, and kept the prose otherwise intact. The simpler version is adapted from Wikijunior on Wikibooks.
Both sources are published under CC BY-SA 4.0, so this page is published under the same licence. You may share and adapt it, including commercially, as long as you credit the original and keep the same licence.
Worksheets, answer keys and printable layouts elsewhere on K5Print are our own work and are not covered by this licence.