The Methane Mamba is a popular experiment for teaching fire safety and prevention… there are only 13 gases that are lighter than air, and methane happens to be one of them. You won't believe the results when you pump a little methane through some soapy water and let it do its dance!
Methane Mamba – Tower of Bubbles
A dancing column of bubbling methane!
The Methane Mamba demonstrates the density of a gas which is lighter than air. Methane gas is bubbled through an inverted, cut-in-half 1-liter bottle of soapy water. The methane bubbles, which are lighter than air, float. A growing column of bubbles rises from the bottle into the air. When drops of water are strategically added to the column, it sways like a snake. For the finale, we set the bubble column on fire, showing that methane is also flammable.
How Does It Work?
Since methane gas is lighter than air it floats upward when it is pumped out of the tubing. Add a little soapy water and it is easy to see that the gas is not sinking… it is creating a dancing, wiggling column that rises in the air. The demonstration is popular for teaching fire safety and in firefighter training because it demonstrates the movement of flammable gases that are lighter than air.
In fact, firefighters can now use this demonstration to investigate new technologies, like a slimy polymer gel that is saving homes from devastating fires.