How To Do Methane Bubbles

What’s the coolest demonstration I do in class? What gets the kids out of their seats and screaming for more? Methane bubbles, methane bubbles, methane bubbles!!!

Picture this…

You put some water and hand soap into a funnel and turn on the gas all while discussing about the four types of chemical reactions previously covered. The gas kicks in and bubbles start to emerge and the kids are not impressed. Bigger bubbles form and some float away. All of a sudden you ignite one and a huge fireball erupts and engulfs the ceiling!! That’s how you excite your kids and get them to remember combustion reactions. After you’ve amazed them for 10 minutes or so, explain the science behind your demo, trust me, they will listen.

Want more details about how to do it?

Materials
– access to a methane gas tap
– a funnel
– bunsen burner
– 2 rubber hoses about 1 foot long
– hand soap
– flint lighter
– 200 ml of water
– tongs
– wooden splints (usually I have 3 on-hand) at least 4 inches long

Procedure
1) Attach the bunsen burner and hose to the first gas tap and the other hose to the second tap.
2) Attach your funnel to the end of the second hose.
3) Light the bunsen burner using the flint lighter.
4) Create a U bend in the hose with the funnel attached and pour in a small amount of water and soap into the funnel (you will have to play around with the amounts but start off small for each). The U bend is simply to keep the soap and water from emptying into the gas tap.
5) Start the flow of gas through the hose with the funnel and let the bubbling begin.
6) Light the widen splint and when the bubbles get large enough, they will float away. When they detach, place the flaming splint against the bubbles and watch as your kids see the coolest thing they’ve ever seen.

There’s a lot you can do with this, just make sure you practice with a fellow teacher before performing it in front of your class. When performing the demo for your kids, make sure you move them a safe distance away and always wear safety goggles.

While explaining the science ensure you highlight the energy released in the form of heat and light and the water produced which can be seen falling from the ceiling. Of course relate this to the combustion equation.

Hydrocarbons + Oxygen –> Carbon dioxide and Water